I've always been a vegetarian, I never ate meat or eggs.
Do you do drugs?
Those PC muscle exercises didn't work for me, in fact, they made me feel terrible, it produced the opposite of what I wanted.
If I was you, I would also consider, REST! TOO MUCH EXERCISE can be your problem, but I doubt it... Just be careful about that.
It probably has something to do with your nervous system! I would strongly recommend for you to do TAI CHI or something similar. There is a thing called sexual Chi Kung, that sounds cool! Tai Chi will help you restore your energy in many ways.
Do you know what Goji Berries are? Also, look up Açai berries.
Physical solutions aside, the most important thing if you ask me, is your MINDSET. Changing your diet or sleep pattern, anyone can do, but changing your mindset, it takes a real man to do that. Don't allow yourself to feel bad! When you feel like this, do something, anything... Find a way! You will feel great. Even if it sounds stupid, DO IT. Doing something is better then nothing, for just trying you will get respect. The most awesome thing about this is that if you don't stop, you'll get far! A little push can trigger a HUGE change. Like the guy says, "Our greatest glory is not in never falling, but in getting up every time we do." It doesn't matter if you are feeling like that right now, what are you gonna do about it? That is what counts the most.
Good luck!