Something is off...

So my husband has been being strange. I noticed the other day that he was being kinda sketchy on his phone- but on top of that he had a rash on his dick. He claims it’s from the heat and possibly having insulation on his hand when he went pee and I kinda believe him cause he’s a roofer so he’s always in the heat and working in attics. Anyways I’ve been offering him blowjobs the past couple days and he keeps saying no. I’m wondering what’s going on with him. Is he cheating on me? Like I swore I saw him delete messages from his Instagram. I feel like he wouldn’t cheat because of the way he is and plus he talks about how it affected his family but like could I be wrong? Why is he being strange? FYI he ALWAYS comes home at night and allows me to have his location (we discussed and decided it was better to share our locations with each other since having our baby in April 2020) he hasn’t been anywhere weird but he obviously works at different houses so i guess I’d never really know. What do you ladies think?