What the !?@# do i say to him?!?

I am on bedrest due to high blood pressure and risk of preeclampsia. My boyfriend doesn't seem to understand how serious it actually is. The other day he went to the fair with all his friends, something i obviously can't do because i am pregnant so i cant go on all the rides anyways. Then he went to the casino the day after. And then a few days after that he was partying and getting drunk with his friends including other girls that i don't know! I couldn't help but get mad because i feel like i am just stuck here and get to hear about all this fun he has with his friends and who knows what he is actually doing. i feel like he has been lying to me about weird things like who was actually at his house. Just leaving random girls names out when i ask who he is with then i see pictures on facebook that his friends post and it makes me feel like ****! And when he comes over he even asks me to do things for him when i really am suppose to be just laying on my left side! i am on "strict bedrest" because of how dangerously high my blood pressure is and trying to hold off having the baby as long as we can. But he just doesnt seem to understand ! and he complains to me about little things like how his knee hurts like i should feel bad. Am i just overreacting? I dont know what to say to him without being a complete ****** to make him understand how i feel. what should i say?