I'm so sorry, Jack, I forget that not everyone knows what abx means!!
It just means antibiotics.
Yes, burning stomach and nausea can both be caused by Lyme. It's not likely that your symptoms will match up with anyone else's, so please be careful doing comparisons.
These infections work on each person's weaknesses in their body, so although there will be similarities, no two people will have identical symptoms.
You can try using ginger capsules or ginger tea to help with the burning stomach. It has been the only thing that has worked for me consistently. To make ginger tea if you don't have the tea bags that can be bought in the stores, you can make a very effective homemade ginger tea.
Heat one cup of water, add 2 teaspoons of powdered ginger (the one in your kitchen spices cabinet) and sweeten with stevia or other natural sweetener and drink down as quickly as you can. This has helped me every time my nausea was really really bad, yet I couldn't throw up.