Please help really need it

I messed up badly but don’t really know how to fix it.

My ex cheated on me and is now talking to someone else, I still love him and always will but he doesn’t feel the same, he’s told me he misses me and he still cares about me, we have been broken up for almost a month now but during that time we’ve had sex twice. I would have him back in a heartbeat but I can’t. We have the same friends so I still see him quite regularly.

I was on the phone and messing around we were talking about me being pregnant I though I said “well I could be” but instead it came out as “i am”then the conversation continued with would you keep it and all this, I personally would never get rid of a baby because I’m not even sure I can have children. He then asked why I was lying I said “I didn’t think I was” then it hit me what I had said from the start. I never realised what I had said until it was too late, we have had arguments before but this has never happened he knows that my head and mouth don’t work together sometimes but this time it’s really bad.

He hung up the phone and has blocked me on absolutely everything, I really need to fix this but don’t know how any suggestions please help