A good mood/satisfaction [This is a double question. I am unsure of Buddhism.SE in relation to posting to questions vs one per post]
So today, Like many teenagers, I went to school, a place where I am surrounded by friends and challenges. Today there were many pleasant moments, both mentally, emotionally, and sensually. 

One thing that isn't unique to this day, is simply getting tired. Over the past few years, I've noticed that getting tired usually makes me more interested sexually, though I think this is either a longing for intimacy, or (more likely) experiencing normal sensory experience as more sensually, ever so slightly. During such episodes of routine tireless that occasionally arise, as is natural I crave sleep. 

Sleep seems like a pretty blissful state, in that it does not really experience any highs, nor lows. I've read that to not experience any desire is greater than fulfilling ones desires. Is this equality 'simply' achieved through mindfulness? How would you recommend pursuing this? 

I noticed that a distinctive attribute of pleasure is that generally, I don't want it to stop. Not that moderation is impossible, but its hard to draw a line with pleasure that is truly satisfying. Are some pleasures more satisfying? Or is the only path to satisfaction enlightenment, being detached from desires?
Regarding characteristics of pleasure &amp; pain, MN 44 says this:


  Pleasant feeling is pleasant in remaining, &amp; painful in changing, friend Visakha. Painful feeling is painful in remaining &amp; pleasant in changing. Neither-pleasant-nor-painful feeling is pleasant in occurring together with knowledge, and painful in occurring without knowledge.


Regarding your sleepiness: once the need arises, I'd try to substitute some of it for meditation, trying to focus on the breath, and not go anywhere else in your mind. Just sticking with it.

If you can get yourself to a state where you can enter meditation and gain refreshment and enjoyment, you'll have made very good progress, and that choice will now be more readily available to you wherever you are. But like anything worthwhile, it takes persistence and dedication to attain. So try to use this motivation for rest that you have right now as a catalyst for developing good qualities.