I avoid stairs now. I have to stop halfway, I'm afraid of falling. I can’t walk as far as I used to, getting out of chairs is also taking several tries. It's hard to get up from the floor. I didn’t notice I was using my hands to push myself up. Carrying groceries is getting harder.
My uncle, now wheelchair bound, began having similar issues but didn't go to the doctor. He was found unresponsive and it is a guess that he was lying on the floor for 3-5 days. This led to major domino of health issues and a steep cognitive decline that is irreversible.
Do not brush this off as old age until all other medical avenues are depleted. PT and OT may also benefit. Request this from you PC if you need a referral for this. Do not take no for an answer.
Good luck.
My suggestion was to talk to your doctor about PT and possibly OT. I think both could help.
In many cases though the old adage of use it or lose it is appropriate. If it hurts when you walk you stop walking and soon it will be more difficult.
Balance is a big issue and having PT to help with balance makes it safer.
Also PT and OT can help you to know how to adjust what you are doing so you are still able.
the other thought is maybe a move to a community where you will get the help you need when you need it. Like Assisted Living facility. Or hiring an aide that can help you a few times a week.