after a half hour of playing angel of death non-stop I got that feeling in my shoulder, like muscle over-use, like after doing a push ups. So usualy I feel this after doing tremolo picking for a long time. Is it normal? I'm playing from the wrist and I feel shoulder soreness. Should this happen?
Drop all tension in your shoulder.

Whats happening is whenever you trem pick, you're shoulder raises a little bit and becomes tense, it's a really bad habit but its easy to correct-

Relax your shoulders.

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If you feel any pain, you must take a rest for 5-10 minutes.

Maybe you have problems with right hand setting?
Maybe yes, i dont know how to say it correct on english ))
Make sure you are tremolo picking from the wrist. Do not lock your elbow/arm/shoulder.

If you can't pick fast with your wrist, work at it! Tension will lead to fatigue and possibly RMI (repetitive motion injury).
The simple answer is you're trying to play faster than you're able too - your technique isn't good enough to play at those speeds yet. So, what's happening is your tensing your arm up and pretty much just spazzing your arm at the strings and hoping your fretting hand can keep up - that's not going to get you anywhere and as you've found is actually bad for your arm.

There's no shortcut here, like always it boils down to practice. First thing you need is patience, and the humility to accept that you're not yet as good as you want to be. Slow down, only play as fast as you're able to play comfortably, keep your motions economical and focus on playing accurately and in time.
Actually called Mark!

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Thanks seagull, you're right. I try to tremolo pick as fastest I can but that fast that I can't handle. I guess I need to slow it down
^^Once you learn to do it relaxed and with your wrist only, I think you'll see a great improvement in accuracy as well. I've spent the last year working on just that -- focusing on wrist motion alone, and I can now tremelo pick for days and not get tired, and my accuracy/cleanliness has greatly improved.
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its the same with me when i tried to learn 'holy wars' about two years ago, it physically seemed impossible, now i can play it pretty easily! practice!!!
I agree i see too many people not agreeing to their skill level.
God why do people constantly have to think they are better than they are.