Am i hypersensitive, or what is this thing?

Yesterday i talked with my girl that we gonna see each other tonight at my place, watch some movies. And later that day she canceled our meeting because she has to go on a dinner with her parents. Ok.. today we talk over phone and she told me that she is gonna meet her friend (girl) tonight, after dinner with parents.

So im all like, "what about me?"

Although, she said sorry many times and tried to excuse herself out of the mess, i told her that im disappointed but not mad...

Is this me being hypersensitive? That right now i feel let down and disappointed over such a ?small? thing.

I do not know how others would react in this situation, would they feel anger, or what? I really just want to go sleep and forget about it even if its just 6pm.

And i feel a bit better now that i shared this with someone.