Ever seen a psychologist? Might help.
I know you're busy and stressed with work, but maybe you could try to find a mom club/group online? I've never been pregnant before, but I do have many baby cousins who I've watched develop in their mommy's womb and talking to my mom's cousins and a few of my friends, I understand being pregnant in general, even with a lot of support, can be extremely taxing on your mind and body, so having to go to work and having a lack of financial and social support can be indescribably rough. Do you do anything social on your days off or at least rest at home? What do you normally do to make yourself feel better? I like warm baths because just laying in the water helps keep pressure off of my tender areas when I'm on my period. I'm sure the similar affect would be nice to somewhat alleviate the aches and pains of carrying and also from having tight muscles that i'm sure you're getting from the stress.
Hope this helps! <3