X Ray is contraindicated in pregnancy. Do warm saline mouthwash twice a day. U can use Stolin gum paint for swollen gums.

Gum swelling is common in pregnancy. It occurs due to hormonal disturbances. Donot panic. As your tell u have pain in one teeth.... Get a checkup done. If there's a cavity or something....u can get the filling done or atleast the cavity removed. If the cavity is deep.... Wait if the pain is bearable otherwise take a gynecologist consent and proceed with the treatment. For gum pain you can use stolens gum paint or dologel if it's severe

If the pain is kind of unbearable then pls visit ur gynaecologist,take his / her  written consent and again visit ur dentist and get the treatment done (mostly it will need RCT)

X-ray is contraindicated.. Might require appropriate antibiotics.do consult physician.