HELP! My 1 week old has an awful diaper rash ๐Ÿ˜”

Brionna
My first son is 11 months old and has never had a diaper rash. Sometimes he'll get a little red but one time using butt cream of any sort and it's gone so this is very new for me.
 
My one week old has a very bad rash and I'm not sure what will help him. The poor thing has such raw, red skin on both sides of his butt and every diaper change is painful. 
 
I have tried butt paste, desitin (regular and extra strength), and Vaseline. The wipes I use are very gentle water wipes. 
 
Anybody have any ideas? I'll be calling doctor in the morning if nothing helps over night because he's very uncomfortable ๐Ÿ˜”