How do i get rid of the shadow over my lip? think it's from birth control and i use sunblock on my face daily

Hydroquinone: Skin lighteners might help, but the strongest ones are prescription. Dark skin people may develop uneven skin tone by using skin lighteners. so I recommend working with a Dermatologist (skin doctor) to get the best results. There are a number of skin bleaching or lightening products sold in drug stores or on-line, mostly containing hydroquinone, that you could try.

Consult your doc: You are already doing the first step, which is to reduce your UV exposure by using sunblock. Your birth control pill is the most likely cause, and a change in the pill type may help as well. See the doctor who prescribed the pill and ask about it. Otherwise, a dermatologist can prescribe treatment to lighten the skin. Start with your doctor.

Melasma...: You are correct in deducing that the hormones from your birth control pills may be contributing to the darkening of your skin. Often, if you stop the pills the skin will fade. Continue with the sunblock. A dermatologist may choose to treat with topical creams. Procedures such as chemical peel or dermabrasion are also used.