Can somebody call the police on me for Giving me money?

I was in desperate need for money (Rent issues) and needed $300 dollars ASAP. So I went online on a dating website and found this guy to give me the money.. At first he was Skeptical about giving me the money but then he felt bad because I kept giving him reasons on why I need the money so he gave it. I gave him my phone number he contacted me and we talked on the phone for about 45 minutes. The next day he took the bus and came to my apartment (he has a car but his car was in the shop getting fixed, that's why he took the bus here) as soon as he got here he sat on my couch and Email transferred me the money with my email address. We didn't have sex or anything, I have proof over text messages and over the internet dating site claiming he will give me this money.. as soon as he left my house the car shop called him and said they are ready for him to pick up his car with the payment of $200 so he called me on his cell phone 10 minutes later asking for $200 Dollars BACK! Just so he can get his car out of the shop... I didn't trust it. What's mine is mine. So I refused to give it back to him because he gave it to me. Why after JUST 10 minutes you want it back just to pay your car? Didn't make sense to me.. Anyway now he is calling my cell phone threatening to call the police and say I STOLE his money and I am trying to commit crime.. But if I have all this proof why would he do that? Won't it just back fire on him, or will I sincerely get in trouble? I am not really scared because I was the one in need of $300 and he gave it to me so am I wrong? Or am I supposed to give him back the money he GAVE to me? Can I get in trouble with the law? I don't have any criminal records and I don't plan on getting any.. Please help what is your input!?!??!