What is this?!

A few weeks ago i noticed a rash type of irritation show up on the back of my thighs. Ive been treating it with cetaphil moisturizing cream for extremely dry, sensitive skin. I put it on every day after a shower, still theres no improvement in the appearance of it. What could it possibly be? Maybe psoriasis? Should i see a dermatologist? Any feedback is greatly appreciated. ☺