I feel pretty guilty about this, anyone have a similar experience?

I don't know what is going on with me. I was a freshman in college last semester. I know it is normal to explore as a freshman and hook up with girls, but I feel wrong. I let myself go and I made out with a girl randomly and then pretty much led another girl on, which is completely unlike me. I started flirting with a girl and I kissed and made out with her and slept in her bed with her (didn't have sex). I didn't intend on having any sort of relationship with her. I don't know why, but I kept sending her very flirty text messages and flirting with her, even though I didn't want a relationship or even a hook up really. She ended up being upset because I "led her on". Has anyone had a similar experience, and is there anything wrong with me? I have never done anything like this before.