Suffering From Back Pain When Bending Or Lifting. Feeling Cold And Numbness. No Relief From Ibuprofen

Question : Hello! I am 27 year old female. I am a housekeeper and laundry attendant at a hotel who recently re-started work two months ago, after a period of 3 months of being off. After returning to work, I began to have back pain in one specific spot directly on my lumbar spine area. My job is very physical and repetitive - lifting/carrying baskets of linen, pushing heavy carts, folding hundreds of towels/sheets a day, bending to make beds, cleaning, etc. I am wondering if I unknowingly injured myself - there was one specific incident where I twisted my back in a weird way to grab a vacuum but no traumatic injuries or anything. The back pain became its worst when doing a lot of physical activity, including standing/lifting/walking/bending, etc. It would also hurt to sit on the couch or sleep at night. Felt a tremendous amount of pressure on the spot on my spine. Frequent urination & change in bowel movements -- constipation, pencil thin stools, and some pebbly stools. Began having some numbness in right bum cheek, and right XXXXXXX pain. Tried ibuprofen but it didn't help at all. I continued to work through the pain for a few weeks even though it was challenging, but eventually ended up in the emergency room. The emergency room doctor thought I had a muscle strain as she could feel tight muscles around the spine and I was having spasms. She asked me to do some simple movement/neurological tests: bending/touching toes, lifting leg, doctor checking reflexes, etc - no problems although I did feel some pain. I took 3 weeks off work to heal. With reduced activity and the 3 weeks of self-care, my back pain got better, but the spot still hurt at times if it was touched. That being said, I was/am still having weird symptoms on the front of my right leg (all below knee) - XXXXXXX pain, numbness/tingling radiating down my leg and foot, freezing cold feeling in those areas, a weird gait when walking. Went back to work for 2 days as I thought I was feeling better but my back pain and leg symptoms came back. Same pattern -- Back pain gone again with reduced activity, but leg pain, numbness/tingling/freezing cold/walkig with a weird gait or minor limp still occurring. Bowel movements still not regular for me (constipation and smaller stools). Now off work on medical leave and trying to figure out what the heck to do. Any recommendations on where I should go from here? These symptoms have lasted six weeks and I'm having a hard time believing it's just a muscle strain at this point... Doctor has recommended physio but I am wondering if it is also time to request bloodwork, urinalysis, stool sample, x-rays, mri, appointment to see neurologist or back specialist? I am freaked out about a possible nerve issue/damage, or another problem (when I use a symptom checker these health issues keep popping up: tumor/cancer, disc issue, peripheral neuropathy, spinal stenosis, spondy something, cauda equina, arthritis, multiple sclerosis etc). With my history of anxiety and depression, I am terrified this is cancer or a terminal illness. People also keep suggesting sciatica due to a back problem or injury but isn't it typically around the back of your leg? I also need advice as to whether I should continue walking a lot/going about my regular daily activites. I don't want to aggravate whatever is occurring but I don't want to sit around either. Thanks for your help :)