You need to get a thorough checkup by a Doctor for starters. Here are some possibilities: You are simply sedentary and out of shape.
You could have a heart, or heart valve problem.
You could have a lung problem, Such as Pulmonary Hypertension
. Have you ever done diet pills? Some of them can lead to this. You could have asthma
, and the inhaler just isn't the right medication for you, or you could have allergies of some sort.
You could have a Thyroid problem, such as hypothyroidism
, where not enough thyroid hormone is getting in to your system. The Thyroid gland regulates your metabolism
, and some hormones.
Regardless, at the age of 17 you should feel healthy and vigorous, it also may be that you are not getting the right nutrition. Go to the Doctor and get a physical. Tell him/her exactly what your symptoms are, and have been.
At the age of 17 you should not be feeling this bad.