Dizziness, loss of concentration, dull headaches, & now fatigue?

For the past year I have had constant reoccurring dizziness (non spinning type), dull headaches, lightheaded, fatigue, loss of concentration and focus, and sometimes on & off nausea. The dizziness began July of last year after I returned home from a cruise. After a couple months of the symptoms not subsiding, I went to a doctor. Since then I have gone to an ENT and even switched doctors who both performed blood work and did ekgs. Everything was normal except an elevated SGPT on the 2nd test, but the doctor said it wasn't very high and that wasn't causing my issues. I have had I guess what you would call 3 "panic episodes", one of which I blacked out and fell but was fine after about a minute, just weak. Ever since then, the doctor has assumed it's anxiety, but these episodes have happened out of no where on rare occasions and I didn't feel like I was going to die or anything. I just had trouble breathing and got severely shaky and sweaty. They prescribed me an antidepressant which just kept me up at night and gave me painful migraines so I went off and they just told me to go to a psychologist. I haven't gone yet and really want to look at all my options before settling on one thing.
I am currently out of school so I'm not stressed and sometimes find that excedrin helps with the fatigue and loss of concentration; but not all the time, recently it just has been making me more nauseous and shaky. I did at one point consider migraines because of family history and even kept a food journal. However, excedrin has aspirin in it, so it does make me wonder if aspirin was actually helping me. I have low blood presure, but not that low; the other morning it was 100/60, but then by afternoon it was 120/80 exact. Usually at the doctor's office it is 110 something.
I have tried cutting sugars and carbs out of diet; no results. It keeps getting worse over time and more symptoms keep showing up and affecting my ability to function and remember things. (1st it was dizziness, then loss of concentration, then fatigue where I'm exhausted and tired despite having 8-9 hrs of sleep) I did get over a stomach flu about two weeks ago, during the which the symptoms were worse and I had to stay in bed, which is unusual for me. I am an active college student, even if I get the flu, I don't lay in bed all day. I have done a lot of research on the internet and am stuck and have no idea what it could be. I'm just wondering if anyone has ever had any similar symptoms/issues and has any ideas, insights, or resolutions as to what could be going on.