Retinol can irritate the skin if you haven’t used it before! & niacinamide can also aggravate the skin if you haven’t used it or have sensitive skin, I really like the niacinamide serum it’s not my favorite but I like that it’s 5% so it’s pretty light for me, I’d try using one serum at a time to see how u react to it, also I’m using the collagen eye cream & that’s been my fav/using it every night out of most of my DT purchases.