How to tell if a guy is actually interested in me or if he’s just leading me on

I’ve been texting this guy for MONTHS on and off. In the past month we have been speaking almost every day without taking a break. We never spoke about anything sexual before and would just have random conversations. A few days ago I made a joke because it was his birthday, so I sent him a snap with the song “birthday sex” playing. He replied saying he would like that and we have been joking around with that since then. The problem is I always text him first and I feel like I’m forcing it. Sometimes I want to talk to him so I’ll ask him a random question. He always replies and we always end up having a longer conversation but I know if I didn’t ever text him first he wouldn’t text me. I’m on holiday at the moment and after the birthday sex joke he said he was waiting for me to come home. I can’t tell if he’s joking or if he actually wants to meet up since he doesn’t put as much effort into speaking to me as I do him. I’m starting to like him a bit and I don’t want to be lead on. How can I figure out if it’s a joke to him or if he actually likes me too?