Im 20 years old and for the last 6 months my sex drives seems to have taken a long vacation. I'm with my boyfriend for over a year now and this is causing a lot of problems in our relationship for instance this morning he asked for a quickie but I declined knowing I would just be in pain and he left with barely a goodbye kiss:(. We have tried it a few times but to start with I'm totally dry and awful tight once we manage to get past that il be OK for 10 minutes then next thing know I get a horrible burning sensation, once he pulls out that's it he can't get back in. other times it hurts if he goes into far then after I could have small traces of blood on my underwear and it would burn me when I urinate. The worst thing about all this is he sometimes says I'm not attracted to him anymore which really hurts me other times he's understanding. Oh and we tried lube last week which worked for good while but after 20mins started wearing off. Both of us are getting very frustrated now with this so please please help me?

There are severe things that could be the problem.

First get std tested to rule that out. Burning can be a sign of stds but doesn't mean you do have an std.
Second I know that when my ex didn't shower first AND RINSE off really good it burned.
Third foreplay can help ease you from pain.
So if all he is doing is quickies to satisfy himself then ypu really aren't going to get any enjoyment out of it
Fourth with lubes you have to keep reapplyinjg them

I already got tested few months back but doc said I was clear. Its not always quickies was just this morning he was in the mood and I felt so bad saying no:( I'm getting to the point where I feel I should finish things because the stress is starting to make us drift apart. I just don't get how my sex drive changed so quickly! One day I'm a sex maniac always wanting it (sorry about that!) the next just praying he won't ask because ill being pain!

If you are getting too much that could be THE problem too. You may need to pace yourself like every other day or less.
I know too much can be painful at times.

Too much that was 6 months ago... now it once a month if we're lucky!

Have you talked about this with your doctor?

No wouldn't know what to say and honestly doctors in my area isn't the best..

Then it isn't enough. Sometimes that far apart your body has to keep readjusting to get use to it.

I no its hard though and doesn't help that I keep working myself up about it

Yeah stress is another factor.
Your tensing your body up which is the exact opposite of what you need to be doing.

I just find it odd to start affecting me after so long and I just keep thinking there must be some other reason!

Are you taking any birth control pills? They can mess up your hormones and your sex drive.