Hello, It may possible to have periodontal disease.
If you have blister on lip so avoid it to scratch.
Also use petroleum jelly to sooth it.
Oral betadine mouth gargles can be helpful.
Avoid hot and spicy foods.
A clinical examination by a dentist should be considered.
Do regular brushing – twice daily, using soft bristle brush and changing tooth brush after every 3 months.
Do flossing, use of interdental aids.
I hope this helps. If you have any further query then feel free to ask. Positive feedback and bonus are highly appreciated. Thank you.