I been going out with this girl for about 2 months now and I truly love her.

Since 4 days ago, we went to the cinema to watch a movie, and the time I spent with her was really nice and I know she also had fun.

After that night, she started getting weird, like she doesn't talk as much as before, and the way she talks to me is different, I can feel it. It's pretty obvious she changed.

When I ask her if she's all right and if anythings wrong she assures me that all is going well with her and that she doesn't know why I'm saying she changed.

I really want to stay with this girl and I'm scared she might be slightly losing interest. She still says she loves me and we're still together.

What should I do to make the weirdness go away?

By the way, we're both 17

2 months and already in love? It's probably lust. As for what you can do, nothing can be done. You both are at an age where the only constant is change.

You sure fell in love fast, but what's happening is you may be getting to see her in different moods, so don't act weird, and insecure ,and worry over what may be nothing.

Instead of worrying, pay attention and learn something about her besides this love thing you seem to be so into. Have fun, and leave the weird questions to weird people.

Yep seeing different moods or she could feel like things are comfortable now and she doesn't have to work on getting you to like her as much or she could be taking you for granted.
Take the relationship slow so you have time to figure it all out and sort it all out before sinking your heart in too much deeper than it is.