What do I do???

So I started dating this guy a few months ago and it’s still real early in the relationship but things going well and all. Before all that I had texted my ex about us bc i had made mistakes that have been haunting me and I wanted peace. Well, he texted me today and we were talking about it, how he had forgiven me and I should learn from my mistakes and all. No talk about getting back together from either of us. After I finished work he asked to call and I didn’t care to say no so he called and we talked, caught up on things (we broke up over a year ago) and we pretty much had a conversation just like it used to be. Now that I hung up I think to myself “I miss that feeling” and he just told me that his feelings for me were stronger than he originally thought. But I really do like my current bf and I don’t want to fuck it up. What do I do?????