In Need of Post-Breakup Advice

So I recently got broken up with during the end of June. I was heartbroken as my then boyfriend and I just moved in together in May and we were together for 4 & 1/2 years. We both just grew apart and didn't have the same priorities. As of right now I'm doing a whole lot better. Especially since school started up again. Just to give you some background, I'm a 23 year old girl trying to finish up my last semester at a university. Anyways, I ended up making an account on Tinder and ended up meeting this guy (let's call him Alan) who just transferred to my school. To make a long story short, Alan and I met up a couple of times before going out on a date, which happened Friday night. Well... I messed up a couple of times. During one of the times we met up before our date, we ended up having sex at this park at night. Afterwards I felt slightly guilty about it since 1.) we had unprotected sex & 2.) I've only slept with one other person, my ex, and didn't want to come off as "easy". But then I messed up again and we ended up having sex at my apartment after our date. I don't know what to do because he seems like an "alright" guy. We get along and everything but I just don't feel that "spark". I think I just feel bad about myself at the moment and just don't want to be lonely... I just wish I was strong enough to not say yes to sex. I also don't get any pleasure out of it either. I guess I just do it out of boredom and for the attention. If he does end up contacting me to hangout again, what should I do so that I can stop giving in? What tips do you have to try and not feel so down about myself?