I had blood drawn over a week ago and my arm is still in a lot of pain when I put it out straight, this has never happened in all the times I've given?

Not right. It sounds like you have a hematoma, blood collection, or venous clot where you gave blood. It is not normal to have that much pain a week after donating blood. You should be seen by a doctor as soon as practical. If your hand is numb, cold, you cannot grip with it, or the pain is so much you cannot sleep, you should be seen by a doctor immediately.
Let me help. Some time when draw blood from your or give you fuild, few thing could happened.1-the vien could leak out form with they hematoma, it wll resolved.2-phlebitis, minor inflamation of the superfiacial viens it well resovled.3-infectionless common, al these could cause your problem, the treatment is simple moist heat frequant 4-5 time a day if is not better check with your doctor. I hope it will help .