Is this normal

I am 20 weeks 1 day and I haven't felt my baby kick on the outside yet which I've heard can be normal BUT with my previous pregnancy I've always felt the baby all over my stomach but with this one I only feel her in my lower stomach and right above my pubic bone I haven't felt her on the outside because everytime I put my hand where I feel her she stops moving (normal?) but i don't know is this normal for her to stay so low in my stomach and not be all over the place I have an ultrasound coming up in a week exactly but I'm really worried