Hi and thanks for using the forum.
What you have described is fairly normal since you have just been diagnosed with bronchitis. It is normal for your heart rate to go up while fighting off infection so don't worry about it. Make sure that you continue to take your antibiotic as prescribed and make sure that you complete it- even if you are feeling better.
Once you have been on the antibiotic for 24 hours you should not really have a fever again. So if you get a fever (temperature over 101 F) then you should notify your doctor. The elevated heart rate may last for a few days since you are still recovering and that is normal. Also, I am not sure if the doctor gave you an inhaler to use, but if he/she did then that can also increase your heart rate.
Hope you feel better soon!
Bridget
Philip -
I wouldn't worry too much about a 112 bpm heart rate. The normal heart rate for a healthy 17 year old is 70-100bpm so its only slightly higher then normal. In times of sickness you can feel stress and/or anxiety. Both of which can elevate the heart rate. Even bmp in the 120's due to Anxiety is not out of the norm.
If you develop shortness of breathe, lightheadedness, or chest pain, a call to your doctor may be indicated, however I wouldn't worry too much. It would most likely just be side-effects of the antibiotics your on. Feel better.