Diaper rash

Jazmine
My 4 month old son has a bad rash to the point where his skin is peeling I normally use Pampers brand diapers but ended up using Luvs because i was trying to get rid of the baby shower diapees I really think Luvs did it because now he's really red...what should I do? I used destin triple strength and Vaseline. Idk what to do!!