I think I’m overthinking this situation. Help?

This isn’t really a big deal but I’m overthinking it anyways. My partner is coming back into town today and I planned out the whole day. Suddenly I get a text from a friend asking if I’d like to bleach her hair. I said “sorry, I have plans today”, she hasn’t replied since. I know she’s not going through the best time right now either. I feel bad since realistically I have 3 hours to kill but I already planned to get ready in that time and adding a whole hangout will disarray those plans. Plus she can see my location so she’ll just see me at home for the next 3 hours. Ive been overthinking this an feel like an asshole. Does anyone have any input?