Deep breath. You are ok and your baby is ok. Its perfectly ok go go and wake up your mum when you are struggling. It's ok for your little one to see you sad about you being sick, he's feeling sad too. This whole situation is wrong. Is there something you can think of that helps decrase your panic, make tea, bake, sew, go do it, it will calm you.
Do you have some anxiety meds? I was very resistant to taking something permanent but I founld something I can take in an emergency when I started to panic very helpful.
Although I really liked my oncologist I recently sought out another opinion. It doesn't hurt to ask. They might have ideas that haven't been considered. Take some time to sit down and study your care and what other options are.
We are all here for you.