One thing to do is just relax. Let your body feel the moment. Explore your partner, and have fun. The more you relax and are not thinking only about climaxing, the better chance you have at feeling it.
If you are thinking and thinking about it and stressing over it, that wont help at all. So just chill out,have fun, and just enjoy sex.

Good Luck!

I don't feel not relaxed. I'm into it, I enjoy it. I just don't think I'm using my imagination enough. Namely because I don't really know how to.
Also, I really want to try to be able to orgasm on my own because my boyfriend has said he kind of feels a pressure to make me come. I've told him to not worry about it and that I don't think any less of him, but I think he still feels a pressure.

I think you need to take your boyfriend out of the equation and spend some time alone because women get performance anxiety too. (I don't mean forever; I just mean that being with a partner will only make you more inhibited and you need to shed all your inhibitions and worries about your performance.) If it hurts you are either being too harsh or you have tensed up to the point that insertion is painful. Relax, give yourself strokes that are soft as a whisper and- I know this sounds weird, but try foreplay on yourself. Get in touch with all of your erogenous zones before getting down to serious business. A small appetizer always makes the entree taste better. =) Take a feather or the tip of your finger and slide it over your lips and face, down your neck, across your breasts and simply concentrate on how good it feels. Then you can move on to your lower regions. I also suggest that you put away the toys for now. Once you get the swing of things you can begin using them again.
If all else fails, try using a pulsating shower head. You can control the temperature- and let me tell you, a little heat can make a world of difference. And you can control the speed/ pressure. You want to start out as gently as possible. Remember to take baby steps and not leaps and bounds.
Good luck and have fun 'training.'

Well that defiantly sounds a lot different than normal, so there's a good chance it's a step in the right direction. Thanks.