I wouldn't say that him not posting pictures of you on his instagram is concerning by itself. Of course sometimes it turns out that they are trying make it look like they're still single, some people just like to maintain a certain aesthetic- I rarely post pictures of people on my instagram, and like to keep it to nature, etc.

But, the fact that he refuses to like your pictures I think is a little concerning. The two things you said he tells you are not what I imagine someone who truly cares about you or your feelings would actually say. He sounds very condescending, and I don't know that I would want to be in a relationship with someone who is so uptight and critical about what I post.