If a girl stops texting back in the middle of a convo or doesn't respond to a text, is she not into me?

MoonMan0129
I became friends with this girl this semester at school and I have started to like her a little bit. We had a class together and one day she gave me her number because we had to do a few projects together. As the semester went on we began to become closer, texting more and more. During our conversations she would always just stop responding to me, in what I thought was the middle of the conversation.

We were able to hang out a few times before school ended and she mentioned a few times how she wanted to see me over the summer. Since school has ended though I have texted her a few times but she has only responded once on her birthday. I know she is busy with her summer class and summer workouts, she plays a Division I sport at school, but I am starting to get the feeling she is trying to send me a message. I don't know what to do.
Updates
+1 y
I thought she would at least have the decency to respond. I never asked her to hang out or anything I just asked how her birthday was. In my opinion whether she is into me or not she could have given me an answer. That's why I am so confused about it.
If a girl stops texting back in the middle of a convo or doesn't respond to a text, is she not into me?
5 Opinion