I met this girl like 3 months ago and I got her number and everything but I was going through some problems at the time so I never really called her , when I finally talked to her again she was acting different, I thought maybe she was acting like that because I never called her but I found out that she was still kind of involved with her ex , I asked her about him and she told me that in fact she was a little confused about the situation and that she didn't know if she wanted to get back with him or not , I told her like an idiot that we could be just friends even if she decides to get back with him. Did I screw up by saying that? what should I do?

I think that shows that you want to be in her life however you can, and that you want to get to know her regardless of her status. I think it was a good move. That's just my opinion though