Hi Chrissy, I don't know about ocular migraines being related to blood sugar. You should ask your doctor about that (or Dr. Google but be careful about that...)
104 fasting is a little elevated. Doctors look for under 100. A non-diabetic's fasting is usually in the 80's. In any case this is what affects your blood sugar in general: excess weight, a diet too high in carbs, not enough sustained exercise (like cardio), family history. It's not just sugar. It's any food made from flour or grains that will raise blood sugar. Corn and potatoes and even all those whole grain breads. Since your fasting isn't critical, maybe just cutting back on any of the food that contains these things would help.
Since you're a vegetarian, please make sure your diet is complete in all the vitamins and minerals you need. Can you eat beans? They're a good source of iron. Low iron can cause hair loss. Low iron and low potassium can cause fatigue. Maybe add some nuts and spinach to your diet if you don't eat them. And make sure you're hydrated because dehydration can also cause headaches.
I don't think that having 104 fasting is high enough to develop symptoms of diabetes (other than the fact that your blood sugar is elevated) but who knows what your daily blood sugar has been for the past few years. If it's been really a lot higher on average during that time, you'll definitely want to bring it down. There is a blood test the lab can do called an A1c which tells what your average blood sugar was for the past 90 days.
Should you get a blood sugar meter? I don't know. If diabetes is in your family, then it might be a good idea. WalMart sells their own brand, ReliOn, pretty cheap. The package comes with the meter and some test strips to start you off. After that you have to buy little bottles of more test strips. Honestly, for the time being, just try to adjust your diet and get your blood results in better shape (iron and potassium), cut down on some of your carbs and then see what your new blood tests show. If you're worried about diabetes, then ask them to include the A1c in the blood tests.
Good luck and I hope you feel better.
diabetes type 2 controlled so far by diet and exercise
very low carb way of eating