What determines the stroke volume in one heartbeat? if i get stressed the volume rise and thats why u get high blood pressure right?

Cardiac output: The cardiac output is measured in part by the strength of the heart (ejection fraction), the blood volume in the body, and the heart rate. Blood pressure rises for a variety of reasons and one of them is stress. Others include pain, exercise, and postural changes. Read Arthur Guyton's textbook of Physiology.

Wrong: Your BP goes up when you are stressed because your peripheral resistance (the "tone") of your arteries goes up. In a sick heart that may make the stroke volume go down. If I were you, I would be worried about the STRESS and not your Blood Pressure or its physiology (at age 22)