Spudlet, I am sorry about your pup too. Our dog has a very sensitive stomach and we have to be very careful about his food. He had pancreatitis which caused quite bad diarrhea and pain. He would yelp a bit when moving certain ways. He recovered well on Royal Canin low fat gastrointestinal food. We now make sure his food is very low fat and he is much better.
I hope the vet can help but I know how expensive it can be even with insurance.
Lemons, I have allergies to many tree pollens and having a lot of symptoms now. I am taking Claritin and a Benadryl at bedtime. It helps but I must say sneezing and coughing gets me down a bit.
If your DS is a toddler, I would think of him as a mini-teen as their main developmental task is separation and individuation. Becoming their own little person. One of our granddaughters was horrendous for about a year, screaming and flailing around. Once she crawled under our hallway runner and screamed for over 20 minutes.
We knew she was safe and we kept an eye on her, but basically ignored the tantrum. She did grow out of it. She is now a very bright and self assured teen.
I should have known from her response when I confiscated a toy she and her brother were fighting over in the backseat of the car. She sat there, opened her book and pretended to read. "Once upon the time there was a mean grandma. A very very mean grandma."
It was hard not to dissolve into peals of laughter.
I know that doesn't solve your issue but you are not alone. If you can get a break, even half a day without responsibilities, it might help.
I hope you feel better soon.