What are your feelings on casual sex?

Around a year ago I was sleeping with someone (no strings), I lost my virginity to him and we were seeing each other for about 2 months. He didn't have much respect for me and I never really felt like I was good enough but I couldn't seem to bring myself to end it. Eventually we just stopped seeing much of each other and then I removed him from my life, since that I've been talking to and slept with a couple of other lads but nothing serious. I met a lad in a club last week, both obviously attracted to each other, we got together on the night but I told him I wasn't going to go back to his because I'm not about that. We've been talking since and get on really well, we'd both like to see each other again but only as a casual thing. Only problem is after the last time I'm not sure that's something I want to do, but at the same time I don't want one bad relationship ruin any others I could have so I'm not really sure what I want to do. Any advice?