My gp ordered stool sample and says im anemic. my iron level is 8 and hemoglobin 116 (can value). i have rapid heartrate and headaches. immed danger?

Blood Loss: Yes. You need to do what your doctor recommends, which is most likely to get to a gastroenterologist and to have a colonoscopy urgently. You are losing iron and you are losing blood. This is dangerous and must be figured out and corrected urgently.

Not immed, but low!: Your HGB is probably 8, which is low, the HGB level would not be 116?, etc? Depending on your symptoms some patients will benefit form a transfusion under 8. If you are relatively health, and you can take iron, your count can slowly start to come up with replacement therapy, but is can take 3 months for new rbc's to develop. Follow-up with your dr for a assessment and plan. Best wishes.