How can I feel better and more energized, in general?

Lately I have just been feeling blah…and I can’t really pinpoint what it is that’s making me feel this way. I’m hoping somebody will have some insight if I provide some basic facts about how I currently live….

I’m 21, I exercise a moderate amount (I bike everywhere, run every once in a while, and lift weights often) and I eat pretty well…no gross boxed frozen stuff or fast food, I cook a lot. I drink a lot of water, but probably not enough since I live in Colorado.

I get a TON of sleep. I’m thinking that might be it? If I don’t go out at night, which about 5 nights of the week I don’t, I go to bed around 11 usually and wake up generally somewhere around 9 or 10 in the morning (I’m almost embarrassed writing this, lol) and I work 25 or less hours a week at a not-strenuous job.

I take vitamins D and C, omega 3–6-9, and a multi vitamin….

What’s my deal? Why am I so sluggish? Should I do some type of cleanse? I’ve heard that built up….sludgy stuff inside can make you feel like this…

Also I smoke 1 or 2 bowls a day, but I don’t think that’s the cause because I feel sluggish even early in the day, when I have absolutely no reason to feel so slow.

HELP? SHOULD I EAT ONLY FRUIT? SHOULD I DRINK 10 BUCKETS OF WATER A DAY? EXERCISE MORE? I hate feeling like this :|

Oh I also have a severe sweet tooth.