Water fasting while on thyroid medication

Hi, I'm on day three of my first water fast, but I have been continuing to take my T3 medication. I'm trying to take it sublingually, but it's possible that some of it makes it into my stomach. Is that going to ruin the process for me?

I should add, yesterday and today I've been suffering from small amounts of yellow diarrhea (sorry if TMI!) - could that be connected to my thyroid pills?

And should I continue or call it a day? Thank you!