Lower bck pain. A bump please advice.

Hi, I am an obese person, i understand i hv to lose weight. I was down with covid. Post being negative i observed some changes in the body. The fatigue level etc. My backbone has started hurting like crazy. I never get lower back pain ever. Unfortunately I felt like there was a swelling and my tail bone was injured. Probably slept wrong so just did apply move and hot pack and ice pack. It's been a week i see no improvement. Infact the pain feel like sciatica as i hv started hv pain run through my left leg just to the thigh. While i am able to walk or sleep and sit however getn up and sitting is causing too much pain..sometimes the pain radiates to my front side of the body right near left abdomen. I am confused should I visit a physiotherapist, orthopedic or a neurologist. The pain in my lower bck keeps shifting to tail bone and then a lil above that. Day one it was like my bck had a bump Please advice.