Girl who likes me is just Went on a date with another guy?

We kind of like each other and I kind of ignored her because I tought she was playing with me and my heart. I didn't want to get hurt, so I let it go, with 2 months of school left. Just 2 hours Ago I found out she really did care about me! Now wat do I do. I don't have her number or anything. HELP!!!