Hiii please answer !!

This has been bugging me all day. I’m not sure whether I have the right to be a little upset about this or not...

Yesterday I stumbled across a girl whom my SO & I have met once, Instagram account. I noticed my partner had liked her most recent pic. He doesn’t follow her.

Now, the reason I feel a little upset is the first time we met her she was quite flirty (towards him) & I was uncomfortable. We spoke about her at a later date and now finding he had liked her pic it has me a little upset.

Please give me some advice 😩😣