Teeth pain. Why is my teeth paining.

Hi, I have pain in the lower teeth from quite some time now. How ever I've ignored the same. Recently my head started to pain in the same side of the teeth. I used to take 2 paracetamol for the same everyday. A few told me that the head ache could be due to the teeth pain, hence I visited a dentist. She checked the all the teeth and said there's no cavity. However there are ulcers exactly where I had the pain. She asked me to close my teeth after which she said my upper teeth actually touches the lower teeth which is not good. There should be some gap between them. The upper teeth is pressurising the lower teeth and hence could be the pain. Also there's calculus in the gap between teeth so scaling and polishing needs to be done.  My gums are extremely black so it could be due to the antidepressants and thyroid tabs I take.  So she asked me get an adv opg. I'm yet to show her this, hence attaching the same. Please tell if it's okay and if it really is okay then why is my teeth paining.