Suggest Treatment For Dryness And Black Spots On Lips

hi, recently my lips became very itchy,dry and red after using this lipgloss. after a few days, the redness was gone but my lips were still itchy. there were also black spots on my lips. now my upper lip and the outer lining of my lower lip looks extremely dark. what do i do? how to stop the itch and get rid of the darkness!?