Ive been feeling weak tired and sleepy?

for some reason i have been feeling sleepy and tired for some weeks now. i have no idea why. i work out every other day for two hours, eat twice a day, sleep for 6-7 hours a day. now i know i should be eating 6 times a day and getting more sleep and food with my workout routine but this is my 3rd year and it has never gave me sleepiness before. i am not on anything either. ive taken the swine and flu shot in the past month if that might have anything to do the the flaws of the vaccines. it has only been about 3 weeks ive been feeling this way. it sometimes goes away and i feel pumped while working out then sometimes while i am i will get sleepy or sometimes i start sleepy and finish pumped up. and in cl ill be falling asleep and other times im good but mostly sleepy. what do you conclude can be wrong?