I Started Getting Pain In My Left Thigh 2-3 Days

I started getting pain in my left thigh 2-3 days ago, especially when putting weight on the leg such as going up/down stairs or even walking. Feels slightly better in bed only when I put a pillow under my knees, but still painful. Don't remember any injury and there is no bruising. I do have osteoporosis. Bone cancer and degenerative joint disease runs in the family.