High pulse, help!

Looking for support! I am new to fasting and yesterday began my first 36 hr dry fast. i started soft as i thought the detox protocol of raising heart rate, massage, hot bath then cold rinse was most efficient but then later read about absolute fasting, and i felt good about taking that route. By around 5 am this morning, less then 24 hours since my last sip of water, i got out of bed with a really dry mouth and a heavy high pulse rate. After reading that those were grounds to break a fast, i began sipping spring water and then a few bites of watermelon. I attempted to lower my heart rate for about an hour, but ended up purging up what i had consumed. Starting to feel a little better except for severe weakness and a slight sharp pain in my left kidney.

To give some medical background, i am 27, hypothyroid, hormonal imbalance, and my naturopath says my kidneys are over taxed (the culprit if i had to guess) but i havent had the means to take the medicines she has for me. other than that i am mostly vegan, quit smoking small amounts of organic tobacco a week ago, was on a juice/ soup cleanse for the past week, but i also dont have a lot of body fat to start with, so that may have factored in as well.

hopefully someone can share their experiences if similar

and also let me know if i am even a candidate for dry fasting, as this method really resonates with me and id be sad to write it off