Lying

So backstory: last year my guy cheated on me. Not phisicaly but cheating with girls on dateing apps and reconnected reconnected an old fling. We've been working on it and while i have my days for the most part it's really good. However I caught him in a lie a few days ago and it was such a stupid lie. Basicaly I asked if he picked up a Gatorade for his sick dog to keep her hydrated and he said he did but when I went to check on her the next morning there wasn't one in the fridge or trash can but the following day when I went to check on her he had gotten her one. I don't care that he hadn't done it the first day I'm upset because he lied to me and if he's going to lie about something as stupid and simple as this what elce is he lying about? Should I bring it up to him? Am I over reacting? I grew up with abusive parents so I get that sometimes we lie when we forget to do somthing and don't want to start a fight. But he should know me better than that. I wouldn't have gotten mad at him just told him to make sure she has access to water. What do you guys think? Do I let it go or ask him about it?