I Am A 70 Year Old Lady. I Am Facing

I am a 70 year old lady. I am facing some strange problem since 3 months, when I used to walk then I feel that my feet are entering in the earth and feel shakiness on the surface. this problem lessen my confidence of going our side the house, specially on the road. In sitting and sleeping posture I am perfectly comfortable. I am neither diabetic nor having hypertension. Nowadays my sugar level used to become low (yesterday my PP recording was 95). Rest of my health conditions are normal. Kindly diagnose what exactly it is. Regards.