i did the same thing your doing when i was working. i put in for a job i really wanted and then worried the whole time between putting in for it and getting it. total freaked myself out. like your doing. and it worked out that i got the job i wanted and it was a great move for me. i was nervous with the move and had to learn some new things. but it was totaly worth it in the end. plus bonus was i made more money. and i was better at the new spot then i was in the old one.
i'm sure that it will work out for you the same way. and you'll do great. i could tell you not to worry but those are just words and your gonna do it anyway. once you get the postion you'll settly back down and be great. and in the very off chance that you dont that doesnt mean your stuck were your at it just means that theres something better coming. and you got to be patient.
as far as the getting dizzy or head feels like it gonna explode when you stand up from sitting. you might try moving from positions a little slower. and if it continues might be time for a trip to the doc for a blood pressure check to make sure its ok. but i would just try getting up slower. getting up too fast causes a change in blood pressure and that could be whats causing the feeling. but i'm not a doc. of anything just my advice. remember that.
I have bipolar disorder, panic attacks w/agoraphobia, social anxiety, diabetes, asthma, and high blood pressure.
~ Life is short but I am not. ~