Panic Attack during sex... 7 weeks pregnant??

Has anybody ever experienced a panic/ anxiety attack during sex? I am 7 weeks pregnant and have had mild morning sickness but it lasts all day and is every day. Obviously this has put a little strain on our sex life but I do try to at least once a week. I was feeling pretty good today and initiated some spontaneous fun. Everything was fine but then I started feeling way too hott and dizzy. I started crying hysterically. I feel extremely awful about it. My husband is more concerned with my well being but I feel like I let him down. If anyone has any tips on how to control the anxiety it would be greatly appreciated.