Gum swollen and bleeds after floss.

Hi, I have been dealing with some jaw and neck pain issue for the last 9 months. It's constant burning and sore pain in jaw under ear and side of neck. Been to several doctors, dentist and no relief yet. I have been told it's either tooth root fracture in #46(only suspect), MPDS and joint degeneration beacuse of  bruxism. I am not using any mouth guard. Does mouth guard help? Told to do physical therapy. The query is, I didn't at all in the last 9 months as I have constant jaw pain. Constantly. So I just brush and didn't floss.today I flossed my teeth and it was bleeding from most of teeth and gums. I see some white tartar at the base of the tooth tongue side. (back). It's present in few teeth upper and lower. Mostly around 5 teeth. After I floss, I see few of my teeth gums becomes red and looks swollen. I don't know if it's swollen, because it's at the back of the mouth.only few upper teeth. When I run over my tongue at the back,can feel puffiness on those gum. is this normal?help.