Hi, staxx.

You might want to try to post your question in multiple forums for the best chance at getting a response. The ones I can think of from the top of my head might be:

fitness
heart disease & heart attack
men's disorders (assuming you are male)

hope this helps you get some answers! Let us know if you're having trouble connecting with other users! -admin

I'm 15, 6', and 160. I'm not as toned as you, but I lift about 4 times a week (3 on a bad week).

First, a lot is 2 words. Anyways.

Sounds to me like you're sore :p

try taking about 3 days in a row off, and see if it goes away.

Also, make sure you're eating a healthy diet to go with that workout.
If you don't have healthful foods and supplements to go with your workout, it'll do no good.