Fatigue, black outs, numbness something in or out of my diet

I am not really sure what this could be classified as, but I am guessing there is something I am lacking. I am 19 yrs old and live a healthy lifestyle; I exercise 5 days a week and have a 2 day recovery period for my muscles. I eat very healthy and I take a daily vitamin on top of B-Complex. In the last few weeks, I feel very weak and tired. I get on average 7-9 hours of sleep. On top of that I have been getting light headed and close to blacking out almost every time I get up. In the last week, I have been getting numb in either my arm or leg maybe once a day or every other day that lasts about 1-2 minutes. Lastly, I noticed today that from my shoulders to my breasts that the veins are a lot more prominent than usual. It was a little alarming. Is there anything I should or shouldn't be doing? Maybe something in or out of my diet? Any suggestions would be very helpful