If you have black or purple anything it COULD be bruising... for the other, don't know. Redness and weeping usually indicates infection for most creatures with infected skin wounds, but with frogs blotchy skin or dark marks can mean a problem too. If they start acting lethargic or don't want to eat you're going to need to seek the advice of a veterinarian. Might look into doing a skin swab and testing for infectious disease. :/

Have you checked the hides to see if they are smooth on the inside or have broken or rough spots in the material? Have detailed pics of the hides and decor in the tanks?