Weight loss? OLP. User! please help me!

So, In feb end my weight was 70.0, i wwnted to keep it constant, but now it has variated upto 66.8(checked today morning), i do go to gym but I don't do cardio, only resistance training, I stay at home and eat healthy food. Apart from this i had chest infection previously in march, for which i had taken antibiotics. Now my problem is i have probably Oral lichen planus(not confirmed by biopsy yet), but i am not reducing my food intake, its same as before 4 times a day, but yes I do take stress :(. Because of this condition, so i have decided to got for a biopsy soon, i dnt have any itching or stinging, but my cheeks feel rough :/. When upper teeth gets rubbed it feels rough.. also coming to stool, i have regular stool at morning, and sometimes after eating I feel like going to bathroom but its fine I don't exactly need to go and it remains fine.. I am a non smoker, non alcoholic and non tobacco user! Please help me!