6 months baby

Just over a 6 month old and 9 weeks pregnant. I feel like such a bad mum :( I’ve got to the point that when my partner goes to work I just can’t cope, my son just wants stuff he can’t have and doesn’t want his toys, I can’t change his nappy as his always on the go, he don’t sleep either. It’s like he gets when his on the floor and cry’s when I hold him. It’s got to the point where I shout at him as I’m so stressed and then guilty afterwards I just don’t know what to do