Just started retinol last night . Why are my forehead lines worse today?

Is this normal? Im only 28 and was starting to get forehead lines, they were barely noticeable but I wanted to get on anti aging before they did. So I started a gentle retinol formula last night (retinol palmitate-supposedly the least potent kind) and to my horror when I looked in the mirror this morning my forehead lines were definitely much more noticeable/deeper looking.. so now I’m scared to keep using it lol