I'm (17m) in love with an coworker (27f)

I (m17) kinda Fell in love with A (f27).

bit of context: I currently have an internship for five weeks, with two weeks to go.

A, One of my coworkers there is really sweet, funny and we share many interests, as well as our taste in music.

So yesterday we talked a bit and she said that she will not be there for the rest of her internship, except for her last dey somewhere in two weeks.

After that we talked a bit about bands we liked and she said that she'll be back in a minute, and came back with an band T-shirt, which she told me she has three times and costs around 200€.

And I think that this is a bit ridiculous, because why would you give away such an pricey shirt, even if you have it multiple times I'd rather sell it than give it to some teen you knew for three weeks.

I already liked her before this happened but now I am overthinking and spiraling down this rabbit hole about why she would gift me this.

I don't really know what to do with my feelings for her, so what would you do?