Baby rash

My 2 month old has little red bumps all over her face. I'm assuming it's a heat rash cause it gets worse when she's hot or is sweating. She has a little on the back of her neck and on her shoulders , we have a doc appt Wednesday, but until then what would you guys recommend to clear her skin? I've been keeping her face clean with just warm water and no soap. Today I decided to use Aveeno baby daily moisture lotion and mixed it with a little Vaseline to keep her face from looking so dry , I'm hoping her face starts to clear up later on today. I'm so depressed looking at her cute little face I just want it to get better!!