[Personal] I'm a teen and have mild acne. Can you help me out and tell me if there is something wrong with the products I use below

Beauty Tips For Body Care
So my derm recommended me this: Tea Tree Soap Tretinoin Cream (at night) Benzoyl Peroxide Erithromycin (i dont buy this due to budget)Is erithromycin important? It costs a bit. Is there something that I'm not doing right or is this just teenage stuff/genetic stuff?I've been using this routine for over a year and it has had gradual albeit slow improvement on my face.I have mild acne on both cheeks although more on the left side than right and a few on my forehead.
Girls Blog 2015
Submitted by reignovermenow