Is this suspicious that my boyfriend came home late and didn’t let me know?

So my boyfriend and I have been together for three years. He recently got a new job at sun run as a solar installer. They travel far for work and work long hours. He started in the beginning of the year that works him a lot of hours and by a lot I mean sometimes 15 to 16 hours it hasn’t happened a lot recently like it did in the beginning but since he’s a team lead now it happens a lot lately. He also goes to school Tuesday and Thursday from 7-10. On a normal day he gets off at 6-7 depending and has to drive back to the shop an hour so like 8-9 he gets home okay. So today is Thursday I assumed he was in class he didn’t message me like he always does but I figured he always runs late and that he let me know later. At 10 o’clock he called me and he said hey babe I didn’t get to go to school I literally just got off of work and I’m driving back home from the shop this was at 10 o’clock at night. I immediately was suspicious because he didn’t let me know I text him earlier and he didn’t text me back I was definitely thinking the worst and thinking maybe he’s just spent the night cheating on me. He was on the phone while he was driving home and missed his exit and was frustrated and tired. Should I be suspicious? Like I said he has worked long hours like this before but he usually lets me know but I don’t know what to believe. Am I over thinking?
Is this suspicious that my boyfriend came home late and didn’t let me know?
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