He acts so weird and confusing

I did a month of no contact and reached out to him a a week and a half ago. We talk whenever I initiate but he barely does. He actually keeps the conversations going, but sometimes, after that, he just stops and shuts down. I bumped into him the other day and before I initiated a conversation he would deliberately try not to look at me or make any eye contact (and I know he saw me). After I initiated he behaved normally, we had fun for like half an hour but then he just shut down and started looking at his phone. Maybe I blew it by doing nc because before nc he would text me all the time, but I told him I needed some time alone and now he’s acting like this.