I’ve never had sex with an ex.

Me and my ex broke up three months ago. I was weak this last week and he messaged me and I confessed that I missed him. He then FaceTimed me for 3 hours and the next day we hooked up. I thought I would be 100% okay with it if it was just sex but now I feel sad cause I didn’t feel the same emotion i had when we did it as a couple. I still love him but it felt like nothing to him (I’m guessing cause that’s how I felt). But he says he wouldn’t be talking to me for three hours or asking me over if he didn’t have feelings for me...

Has anyone had experience with this or can anyone give me advice?