Adrenaline Rush - Heart Pounding

hi guys if I get an adrenaline rush, like racing someone in my car on the highway, my adrenaline hits real hard and sometimes it's hard to function. My heart just pounds real hard. And when I get nervous it beats very hard the beats are visible through my shirt. I'm 19 , about 185 all natural body builder... 5'11 prob 8% bf?

I have a constant pressure on my head, no sinus junk... I don't do alot of cardio ... but I probably should when i get my gym membership back...

Only meds I've taken is Accutane, no2, ....

I can also feel veins throbbing in my head sometimes...

any pointers?