Because hypertension is a silent disease you may feel fine but be a walking time-bomb. Most people don’t even have any symptoms or may only experience a mild headache and then suddenly they are in a crisis or were diagnosed with a secondary disease caused by the hypertension. Getting diagnosed early and keeping your blood pressure controlled can help prevent this.
Hypertension adds extra work to the job of your heart and arteries. This is not a problem if it is short term and your body has a chance to recover, but when you have chronic hypertension your body never gets a break. If uncontrolled hypertension continues over a period of time, it can lead to damage of the blood vessels. Especially damage to the heart and arteries (the blood vessels that deliver oxygen and other nutrients to your body) and these will eventually start to fail. Other blood vessels involved could be in the brain, heart, and/or kidneys, resulting in a stroke/brain damage, heart failure, or kidney failure. The biggest risk is that hypertension increases the risk of a heart attack.
So, why should you be concerned about your blood pressure if you feel okay? Secondary problems are less likely to occur if blood pressure is controlled. The reason you feel ok is probably because your blood pressure is normal because you are treating it. A sudden crisis caused by uncontrolled hypertension can lead to malignant hypertension in some people. This is an extremely high blood pressure (usually over 200 systolic) that causes swelling of the nerve behind the eye (the optic nerve). This is considered a medical emergency. Many of your other important organs are in serious risk of injury including your brain, eyes, blood vessels, heart, and kidneys. The blood vessels of the kidney are the most susceptible to injury and damage may be permanent.