Get out while you can!!!! See my answer to "Hitting the Road", who asked about knowing when to get out of a relationship. In my opinion, there is nothing more detrimental to a person's self-esteem than a possessive guy telling you what you can and can't do. At first, it's not bad. In fact, it makes you feel loved and protected. But it can get out of control. And you feel suffocated. Then you stop being happy because you can't be yourself.
Evaluate this relationship. Maybe he wants more of a commitment than you are ready to give. Maybe he is experiencing anxiety because you are all he has, while you have a lot of other things going on in your life.
But probably he is just too jealous and you need to let him go.