Is my boyfriend nitpicking me or am I looking for whats not there?

It’s very subtle but I notice my boyfriend will have days where he says little things, in a certain tone of voice that seem like he’s trying to mask some insecurity by bringing me down.

For example, we went thrifting one day and I found a game for $8. Then I noticed the same game, but for $7, so I exchanged them. He has now brought this up on 3 different occasions, mocking me for being so anal over one dollar.
But when we went grocery shopping and I got a type of cheese that was a dollar more, he made fun of me for that! Saying he can tell I’ve never been poor. How can he make fun of me for saving a dollar on a video game, but wasting a dollar on cheese?

One more example is when he was sick last time, he laid around on the couch all day for a week. But when I’m sick he always says stuff like “Ya know laying around won’t make you better” and insinuating that I should exercise when I can barely get out of bed.

What do you think of this behavior? I’m I right to get mad about this?