Okay confusing one here. I met a girl called Lisa a couple of weeks ago, she knows a few people in my group of friends and we met like that. I've been gaming her but not full on gaming her, but I mentioned to my friend that I think she likes me and he took her to one side to ask her (He did this automatically, i said nothing) and apparently she fancied someone else in our group.

Anyway, ever since I said "It's a shame you're not older, you'd so be my type" shes been qualifying herself and literally will not leave me alone. Now shes saying I rock but she sucks, etc.. etc.. What do you guys think?

Keep her chasing you. When you think it's getting too much then you can assume interest and maybe go for her if you want.