Help needed

So a girl I've known for two years but have never had a conversation with more than hi and bye, sent me a dm on Instagram. This happened a day after I had initiated a conversation in person during which she gave me her phone number.

I suck at these things, but I have a feeling she might be somewhat interested. What do you guys think?

Are you serious? She's very serious.

I can't wrap my head around the fact that she could be. We tried meeting up twice but didn't work out. After it didn't work out the second time I didn't answer her text. I don't know what to do..