Any tips? I’m desperate.

I’m pretty much with my 14 month old son 24/7. My husbands always at work/busy and I never have anyone else watch him just cause I don’t have anyone I trust except my mom or my sister who are an hour away and work. Which I don’t mind but for the last month about he’s been in a phase where most days he does not want to be put down. I mean not at all. I can’t put him in a play pen for a few minutes to get things done without him shrieking at the top of his lungs the entire time. And sometimes he doesn’t want me to even put him down to play with him or even sit down with him. He wants me to walk around while carrying him for HOURS. I’m at my wits end I’m gonna lose it. I go to school from home and can’t get any school work or house work done. On top of that I’m 36 weeks pregnant and it hurts to hold him so much.

What do I do!?