It can be due to vitamin B deficiency or allergic reaction. Take some vitamin B complex for some days and see if your symptoms improve. Also avid applying any lipstick and take some Beandryl and apply some Vaseline on the lips. Topical creams like tacrolimus ointment (Protopic) and pimecrolimus cream (Elidel) are also useful but are available under prescription.
It is very difficult to precisely confirm a diagnosis without examination and investigations and the answer is based on the medical information provided. For exact diagnosis, you are requested to consult your dermatologist. I sincerely hope that helps. Take care and please do keep me posted on how you are doing.