Medicine diaper rash help!!!

I have an almost 1-year-old that just started amoxicillin yesterday and she keeps going number two a lot. It is more watery than normal and it’s giving her a really bad diaper rash. We use already a butt paste and Lotrimin every changing to help the rash go away. Nothing seems to be helping and it’s only getting redder and more sore. What do I do?!? She has eight more days left 😭😩😭😩