Skin Problems from New Diet?

I've been vegan for over a year and due to depression, I recently started to incorperate cheese, eggs, butter and milk. At first, my stomach did not feel good any time I ate an animal product, now my stomach is fine. But I recently started to get super itchy in places like my neck, armpits, vagina and arms. And even some red bumps have appeared like a rash. I think this is from eating animal products again, should I go back to being vegan? Or should I wait it out?