Did I do the right thing?

I have a friend who always guilt trips me whenever I can't hang out. This past weekend on Sunday it was her birthday party at a restaurant/hall. I had full intentions on going and bringing my boyfriend along. On Saturday night after we had went out to dinner, my boyfriend didn't feel well and he began throwing up and this continued on through Sunday morning. So I texted my friend to let her know he wasn't feeling well and that if he feels better at some point during the day so that we would try and come down to her party, even for a little while but if I wasn't able to make it I asked her if I could take her out this week and treat her to dinner. She texted me back "idk" and that was it. Haven't talked to her since and we didn't go to the party. She always gets angry whenever I can't go somewhere. I had full intentions on going to her party and didn't know this was going to happen so is she right to be mad at me because I wanted to make sure my boyfriend was okay and wanted to take care of him or should I have just went to the party on my own even for a short visit? This has been bothering me for a couple days now. Did I do the wrong thing?

For what it's worth, the party was a 50 minute drive away.