Don't worry, when I take Nascent Iodine my heart rate goes up considerably and I get real hot. It's rather refreshing considering I've been a walking iceblock the last few years before discovering Iodine.
Our heart rates fluctuate during every 24-hr period depending on what we're doing, whether we have eaten recently or not and when I exercise my body gets warmer and my heartrate goes up for the next day or so. No issues. Just a healthier body.