Are we even exclusive? Should I just forget him?

I really need help. I can’t believe its gotten to this point and this might long but here goes. I met this guy on OKC and he was quick to ask to switch numbers and communicate offline. During this time he asked texted everyday after work even though he was busy with work and after a few days he asked me out on a date but I was busy so we agreed to move the date to the next week. During that 1 week before the first date he called me the night before and we shared stuff about ourselves, him more than me, he told me a lot of personal stuff and I felt for him.

Fast forward the first date was amazing, I knew he had a complicated past where all girls screwed him over but he seemed like a kind genuine guy and he could not believe that I was a girl who had never touched a drink or smoke, that I was that good. At the end of the first date we hugged and the day after he asked me out on the second date the next saturday and we went to his place and had a really nice time chatting , during the time one of his exes he told me about texted him and it was at that moment when I felt hurt by the intrusion I knew I really liked this guy. He apologized and when I asked if he still like her (about to get cheesy here) he put my hand over his heart and said my hearts beating this hard because I hate her that much. I wasn't sure what to say so I just nodded.

After the second day its been 2 weeks now and unlike the first week, he stopped texting me, hasn't made an inclination to ask how i am unless I make the first move. Occasionally he snap chats me but that was only twice. I feel really hurt because I think about him all the time and ask him what he is doing, but he has mostly stopped and today was the limit when he posted a (nothing steamy) but a picture of him and a girl he works with on instagram, the girl is laughing and he wrote "Happy looks good on you" he's crouching down smiling and she has his hand on his head.

I'm sorry but after 2 weeks of second guessing his feelings this just hit hard and it hurt. Is he playing me. Should I just end whatever this is, should i even bother calling first and talking to him or would that be too soon. My birthday is next week too and he knows should I wait until after that to make a decision. He's a pisces I dont know if that matters lol?

I forgot to add something before the second date we talked on the phone when he reached out to me about something when i texted him how it went and he asked to chat and told me if this was okay because he though we had established something between ourselves ... that we liked each other and on the phone he told me he felt like I was a genuine person, and even said (I'm the tradition girl lol) is it okay if we date for 2 years before jumping into marriage. I was a little shocked at the marriage thing and i was like I'm not worried about that for now and that I was fine with it. I'm so confused how did he go from this to what acting like the past 2 weeks. Is he screwing with me or using me.