Baby growing rapidly

Hi mummas and papas

I’m 24+2 and been told my little boy is growing rapidly and very fast he is currently measuring 2-3 weeks ahead 😱 because of him growing so fast he hurts when he kicks on the left side really bad under the ribs but my uterus isnt measuring that big at all yet, he is also draining my energy and I’m constantly tired and my iron and blood pressure are dropping all the time. Any one else have this and what they did to help I’m already iron infusions weekly to help keep them up and drinking about 3-4 litres or water a day but not making any difference. I feel miserable this pregnancy and can’t rest because I already have 4 year old twin tornados 😴😴