<human>: Give me the gist of the text in a nutshell

I've been meeting this girl [17] since months ago and we started as friends, later as friends who kiss each other and later we could not see each other so often because ours schedules. But we still chat by phone but the emotion felt of a little because we only chat by phone.

Today she posted a picture of herself in Instagram showing the belly. Something really rare in her since I know her. But she looked really hot in that outfit and sincethat moment I feel really strange like angry and sad at the same time but feeling impotence. I don't know if it's jealous and why. Help me reddit please
<bot>: A girl friend who i'm a little into posted a sexy picture of herself and i'm feeling weird after saw it.