Hi..
Welcome to HEALTHCARE MAGIC..
I have gone through your query and can understand your concerns....
As per your complain small bumps over the lips with a history of having cold sores that is a viral infection caused be 
Herpes simplex virus 1 can be  due to recurring episode of herpes itself..
In case if you think it is not cold sores other cause can be 
allergic reaction to any food,medicine or cosmetic..
But a confirmation can be done only after a clinical evaluation and investigations like 
blood test and if the bumps are fluid filled culture can be done..
In case if it is cold sores topical and oral anti-virals like 
acyclovir can be advised..
In case if it is due to allergy anti allergics like Levocetrizine, allegra or benadryl can be advised..
Topical application of steroid ointment and cool compresses will help..
As of now you can take 
Ibuprofen for relieving pain and do cool compresses over lips.
Hope this information helps..
Thanks and regards.
Dr.Honey Nandwani Arora..