You need to drink plenty of water and also keep your lips well moisturised. Apply a medicated lip balm with a sunscreen to avoid damage due to the sun.
If your lesions still persist, it would be best to see a skin specialist for a confirmed diagnosis and to rule out any other cause of the spot.
Are you allergic to any substances? What symptoms do you have other than the lip lesion? What is your age? Do you smoke?
Let us know if you have any other doubts and also about what the specialist advises.
Hope this helps.
I had the same issues with dry cracked lips also itching and small blisters, I found out from the Allergist that I could be experiencing Contact Dermatitis which can be caused by all sorts of things such as perfumes cosmetics/ lip glosses, nickel, dyes, rubber etc. It was recommended that I go to the dermatologist and get "Patch Testing" done to see what's causing the reaction and I will be going soon, I will come back and let you know what the results are, Hope this helped someone.