Thank you everybody! I already felt better anyway, but I feel even better after having read your posts :p
First things first, the iron transfusion was a success! That alone is actually quite a weight off my mind. I spoke to the haematologist beforehand. She seemed very nice. She explained that before the clinic had moved onto something called Ferinject, they had tried to avoid iron transfusions except as a last resort due to bad reactions and other complications. She was really praising the stuff, saying that nobody had had a bad reaction to it. Well, I managed to have a bad reaction <_<. I actually felt quite dreadful for the first hour. In the beginning I itched quite badly and where I had been itching, bumps came up - hives, I think. Not very many, about 4-5. I also had back pain at one point and, more worryingly, chest pains. But I never felt suffocated or that I couldn't breathe, which I did when I had an anaphylactic reaction last time. And the regular check ups showed everything as being normal.
Just as well the haematologist decided to be careful, though, otherwise it might have been worse :-/ She gave me half the normal dose (so I have to go in for a second dose in two weeks' time) and the infusion was started off at a very slow rate and gradually speeded up. At any rate, if you are like me and can't tolerate iron, then I recommend Ferinject. I have had so many bad reactions to iron over the years, that if I can tolerate this stuff I should think almost anybody could. I don't know its generic name, but *checks leaflet* it's a Ferric carboxymaltose compound if that helps.
I already feel physically better; although when I got home I did manage to lie on my bed and burst into tears <_<. But it was a short-lived depression! It was a delayed reaction to quite a difficult morning, I think. (Had a bit of trouble with my mum and dad, too =/)
@MMMNavy (and others) who mentioned B12. I can't believe I forgot to mention that to the haematologist. I felt so stupid afterwards when I remembered, but it was too late =/ I'll have to mention it to my GP now and ask him to do a test instead. Or I could ask for a test next time I go to the hospital; they didn't take my blood today but they said they would next time I went. Just have to find a way of engraving it into my brain so I don't forget >_<
@Rider - My haematologist did ask if I'd ever had a blood transfusion and I said no. I have a feeling the NHS wouldn't give a blood transfusion for anaemia unless you were at a dangerously low level. But it's probably the fastest way of curing anaemia that there is. My haematologist did say that, even with the iron transfusions, if I had an active inflammatory process going on my Hgb probably would rise only to 10 or 11, instead of the preferred 13 :-/
Sorry for my late reply. The above is the unfinished post that I referred to. Meant to reply sooner, but I had the severest breakdown after getting back home. I'm still shaken by it and don't feel out of the woods yet. I don't even know what triggered it, really. But ironically enough (ironically, iron... get it? <_<), I think the iron gave me the energy that I had previously lacked to get so energetically upset with. (I'm certain it's already made a difference; my legs feel calm and tingling-free. Didn't realise how much I was jiggling them about before.) Going back to what MMMNavy said about mental and physical health, I developed a theory today that, just as I neglected my physical health and it came back to bite me, so I neglected my mental health and that, too, has come back to bite me :-/ I would like to try therapy, but it doesn't really exist on the NHS and I can't afford to go private =/ I did get to see a psychologist for a single session last year. He seemed to be a good guy, but one session? Really, I wonder the NHS bother with mental health at all sometimes. They can't even begin to afford to pay for the intensive help that mentally ill people need, but that's another issue. *climbs down off soapbox...*
I'll try to wrap up this post, because it's getting longer and longer...
I made an appointment with my GP for next Monday, so I'll ask about B12 then. And mention today to him as well.
@sniper - Thank you :p By the way, I did read your diabetes thread. I'm sorry you have to deal with that on top of Crohn's, but I hope the insulin will make a big difference to your blood sugar levels. I had an uncle who lived a good life until nearly 80 despite having type 1 diabetes for 55 years of it. He'd have probably died about 50 years earlier if he hadn't had injectable insulin.
@Nanners and vixen - It's hard to see how I could get this low on iron without also getting on low on B vitamins as well, so I'll look into taking a general Vitamin B supplement. I'm not too optimistic about getting B12 injections, so I might have to take that in pill form too.
In the meantime, I do have a few valium pills that my GP prescribed to me a few weeks ago. I have resisted taking any until now, but I think I'm going to take one after posting this and try to go to bed in a relaxed frame of mind. Thank you again, everybody, and apologies for inflicting an even longer than usual post upon you all! <_<