I've forgotten, is it normal to feel pressure on my forehead and lower…

I've forgotten, is it normal to feel pressure on my forehead and lower abdomen even when sitting or lying down? When I lift my daughter, I feel a push in my lower abdomen on the left side, like something is clicking in the muscles, or maybe that's the baby ? It seems like there wasn't such pressure on my lower abdomen during my previous pregnancy, it feels like the baby will pop out of me now, at week 15 I had an ultrasound, they said pelvic presentation head down, placenta on the front wall. Could these strange sensations be due to stretching uterus? Or are they symptoms of symphysis? Can you tell me how your pregnancy progresses at week 18?