Wait for him to contact you, but I agree it sounds like he may be losing interest.
Here's a word of advice from someone who has only been back in the dating world for a tiny bit longer than you: I never realized how many younger men want to have sex with an older woman. I routinely get hit on by men in their late 20s - 30s. I am >40. Enjoy it if you like, but keep in mind they are probably just looking for sex, which would explain why this guy is cooling off after not getting any.
Relax... I'll need some information first. Just the basic facts - can you show me where it hurts?