I've had a fever, sore throat, cough with green, blood tinged mucus for a few days. also a mild pain at the bottom of my chest. should i go to my dr?

Bronchitis: Bronchitis or pneumonia developing . Would be wise move to see physician.

Yes: You may well have bronchitis or pneumonia that might require antibiotics.

Yes, ? pneumonia: You certainly should see your doctor. Hopefully, you just have a virus, but your signs and symptoms are worrisome for pneumonia. You need an exam with a sputum culture and probably a chest x-ray.