Anxiety I can’t feel my baby

I recently fell at work landing on my knees and hands, I’m 21 weeks and my baby hasn’t been kicking as often as he use too. I feel more of a pressure than anything on my tailbone but I haven’t felt the flutters and rolls that I did a week ago...I called my doctor she said I should be fine but I’m having sooo much anxiety. I’m scared something may be wrong but I don’t know if he’s in a different part of my uterus that I just can’t feel him. I tend to carry him more in my back than in my stomach so idk if he’s just hanging out back there and I can’t feel him back there. What do I do?