Product “Layers”

I constrantly look for the “like” button on your posts and replies to forum questions!  You should add that option!

Question is product layering.  I’m often too lazy to do morning routine when travelling, so it’s wash, BB and go.  But at night I’m able to apply product.  Generic Retin A, Vit C (Ascorbic Acid 20% serum) and a hyaluronic acid-containing moisturizer.   BHA/sal acid on my nose – large pores and blackheads.

I know to be sure to rub in well (but gently) and let each layer soak if applying more than one.  But am I wasting Vit C if I apply after Retin A?  Or the Retin A if after vit C?  On weekends it’s AM -C and PM -RetinA.  Both times I still use Clean and clear Sal acid on nose.  And moisture around eyes.

Thanks for any input.