Husband called me a dead fish

My husband and I got into a very heated argument. Things were said on both sides that’s were awful and that we clearly didn’t mean. I know we both regret it but one thing he said was your a dead fish in bed…. We have a pretty good sex life. In 6 years he has never once discussed with me that he isn’t happy with me in bed etc. but that’s not something that just pops in your head during an argument. I’m so uncomfortable now and don’t even want to have sex with him I’m so self conscious. Advice?