Melanoma sking cancer

Hi, ive recently been told ive got melanoma skin cancer but ive had it removed and been given the all clear, but ive been having problem with forgetting things & im worried as i feel like its getting worse, is this related to the melanoma? 

I am still under the hospital as I have to be checked out every 3 months. I've not spoken to anybody about this as I feel like people will just judge or say your young its nothing.

Thank you.