Hello, Red spots at the back of the throat is indicative of infection. Get clinically examined by an ENT, who did tonsillectomy for you to rule out any complication other than infection. Strep throat infection is commonly treated with a course of Cephalexin. You can take acetaminophen, one stat when needed after food to get relieve from pain. Gargle with warm, salty water at least twice daily. Get plenty of rest. During recovery phase you may get sore throat, it will resolve with a weeks time. The scabs fall off as the tonsil wounds heal. Some bleeding from the mouth is usually a sign of the scabs starting to break up. Avoid taking hot, spicy, hard, or crunchy foods, as they trigger sore throat & also cause scabs to break before time. Take fluids and cold food. Take soft food, like oats, porridge, etc., to limit pain throat. Colder foods such as ice cream, or juice may also be comforting. Take care. Hope I have answered your question. Let me know if I can assist you further. Regards, Dr. Nupur K, General & Family Physician