Welcome to HealthcareMagic forum,
As you mentioned you have mild symptoms over your lips ,along with burnt like skin lesion over lips and lastly you had two episodes of the same....well this all goes towards herpes
labialis...and is associated with stress
too...The best option is tab acyclovir
which needs to be taken for 7 days if your problem is very occasional....or else if you get more that 6 episodes in a year, then the tablets needs to be taken for nearly 6 months.So, consult a dermatologist
for proper diagnosis and treatment.