Experiencing Severe Fatigue, Do not know why

[mymicsoundsgoodcheck1]

For the past few years I have struggled with mild fatigue, which I believe at the time was caused by stress/anxiety I put on myself. However, for the past 5 or 6 months my fatigue has gotten much worse and I am not sure why. Fatigue is the main symptom I have, but other symptoms include black eye floaters, somewhat sensitive to bright sunlight, dizziness upon standing after lying or sitting, constant yawning, I force myself to workout even though I am usually much too tired, poor concentration, and a lot of the time I can feel the exhaustion in the front/top part of my head.

I do not have any problems falling asleep but wake up every morning feeling as though I've been hit by a bus and got no sleep the night before. I also do not have any problems with diarrhea or vomiting, however for about 3 months last summer I had on and off stomach pain that I took Prilosec for that eventually just disappeared.

In addition, it seems as though the worse I feel the lower my sex drive is and I sometimes get acne, but I am not sure why sometimes I feel noticeably worse than other times. I eat healthy, workout, get enough sleep, drink enough water, etc. I have had physicals and blood tests done, have had my heart checked and x-rayed, etc, but everything came back negative. I have minimal stress and anxiety now, but feel even worse than I did a year ago. I've been doing my own research online but am still not sure what could be causing this. I am a 21 year old male.