Hello,
It can be due to inflammation and infection of small hair follicles present around the lips. Keep the area clean and apply some topical antiseptics. Also use an antibacterial soap or mild soap like dove. Avoid any kind of cosmetics. Topical antibiotics such as mupirocin or neomycin containing ointment are also useful. In case the symptoms persist then oral antibiotics may be needed. Please consult a dermatologist in that case.
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.
I suffer from the same problem as you. I have looked at the picture and it is defiantly not a cold score.My advise would be to try tree-tee oil, which will get rid of the acne in a couple of days, you can get this from all good herbal shops and unfortantly you can't do anything about getting ance and it can be a nightmare when it happens!!