There are several reasons for bad breath
, most commonly it is tartar
in the mouth. You need to get scaling done to remove the dirt and it should improve your breath.
Most of the mouth washes contain alcohol / chlorhexidine
as an ingredient which results in burning sensation in the mouth. if you already had mouth ulcers then it would have caused severe burning and irritation. I would advice you to stop using that mouthwash and revert to non alcoholic mouthwashes such as betadine
mouthwash. This will stop the burning and you will feel comfortable. If the irritation persists after a couple of days then i would strongly recommend you to visit a dentist
for the same.