What is wrong with my cat?

Today my cat started to vomit some brown orangey liquid and a hairball. Is something wrong with my cat?? Btw I just bathed my two cats (the other one hasn't been vomiting) 2 days ago and my cat (the one that is vomiting) was sitting on the window that was open right after he took a shower but it wasn't that cold outside. What is wrong with my cat?? I need tips on how to care for it or some medicine thx!!