20 weeks pregnant and having upper abdominal not too painful but uncomfortable but goes to upper back too is this normal?

Talk to your OB. Upper abdominal pain rediating to the back can be a sign of gall bladder problems which are more common in pregnancy due to the high hormone levels. Discuss your pain with your OB who will most likely order an ultrasound of your gall bladder. Even if it is a gall bladder problem, intervention will be delayed until after delivery unless it becomes severe. Best wishes to you and the baby.