How do I tell my husband triggers me sometimes while having sex?

I somewhat recently had to confess to my husband that I have been sexually assaulted in the past. We’ve been together for more than 5 years. Honestly, I never really planned on telling him. I had never told anyone. It doesn’t affect me anymore on a regular basis and if it does somehow pop into my mind I can usually get over it quickly. However, one night we were being intimate and he covered my mouth with his hand. I freaked and basically threw his hand off me. He knew something was wrong and asked if something had happened. At first I denied it but eventually gave him some details the next day. He was pretty much the model husband for receiving news like this. Over time I have mentioned some things that can trigger me while we’re having sex—heavy breathing, the smell of beer, if it’s too dark I can’t see his face, etc. He does his best but he’s human and I guess he forgets at times. Some days I can handle it better than others and we can continue on fine. Some days I can’t and I want to point it out but I don’t want to hurt his feelings or make him self conscious. Most of all I don’t want him to treat me or our sex life differently. Would it be helpful or harmful for him to know more details? It happened while I was in college. I had never had sex before or had any experience really. I was in pretty bad shape afterwards as the guy had punched me a few times and was extremely rough. Should I keep all this to myself? I don’t want to make anything more difficult for him.