What to do in your first relationship?

Homophobes, bible thumping Christians please stay away.I am looking for advice and not someone telling me that homosexuality is wrong. I was born this way!!!I am a 18 year old man currently involved in a relationship with someone almost twice my age. We are not exactly a couple yet and we would like to keep it that way because it will interfere with my studies. Before all of you judge, this is a very good single man( with no wife or kids) with a career, we know each others families, and he does not force me to do anythingI know this part is very judgable but we first met through a gay dating app called Grindr, I first met him through a hook up. We decide we really liked each other after that night, so we kept meeting each other after that, not only hookups but just hanging out in general. It has been three months already, he has clearly expressed he has feelings for me through the things he said. I like him, but I dont know how if I can trust him yet. He's a doctor, so I pay him for my gluthatione injections. Could he possibly only like me for my money? We were friends with benefits before this... Could he only like me for the sex? He doesn't show any signs that he is taking advantage of me but the thoughts just worry me.I also feel I am getting overly attached to him. Before I didn't really mind if he didnt text me or not, but now I get really anxious and worried if he replies slowly or  doesnt text me. I understand I am still young and unemployed, He's a busy  adult with a job and life. I've never been in a relationship in my life before, I've never been so attached to someone in my life. I'm scared I might say the wrong things or come off as too clingy. I really dont want to lose him.. he's a really nice and good guy.What to do..Break off this relationship so I can stop this pain? Talk to him about it? Try to take it further? I'm blind now and need guidance. In your opinion..Is this relationship immoral? Would a relationship like this ever work out? What you think?