strep throat recovery

I went to ER Thursday night due to increasingly painful/annoying aches in my back and both legs. I had a soar throat but no coughing or sneezing/congestion at that time. It hurt to swallow. I was tired but couldn't sleep because my legs were aching especially when laying down. If i was walking, it was fine.

By the time I got to the ER I was hunched over in lower/mid back pain and had tears from the pain. I laid on the cot in my winter coat, hat scarf, and gloves in fetal position and was comfortable in regards to temp. If i took my coat off I got the chills. I had no fever tho. 98 degree temp which is consistent with what I had at home earlier in the day. They gave me an injection of ibuprofen/something to help the pain so i was able to sleep. I was given a rapid step test that came back neg but they said 10% of the time they're not accurate. I was given an injection of penicillin they said would be a time release type thing. I cried both injections from the pain but i never do that! i was dehydrated also which they said was the reason behind my pain severity.

After some water and about an hour of rest, I took off the layers of clothes and felt a ton better! I was discharged w/Ibuprofen 800 3 times a day (NOT a PRN). So I have no pain but my throat has gotten worse. Lots of flem, coughing at night especially (dry cough), and in the morning (productive cough). My mucus is sometimes green but sometimes has spots of blood in it. I have concerns as to whether or not the penicillin is working. How long does strep last? I'm on day 6. I have a humidifier which helps. I've sanitized everything I can and even got a germ terminator toothbrush cleaner. Am i just playing the waiting game now or what? Should I be worried about the blood since it's not a lot? What sort of symptoms will I get when I stop taking the Ibuprofin 800 (which seems to be a high dose)? The ER also said to follow up with a Dr "without fail" 1-2 days after and never did due to insurance/$ concerns. However, at this point should I make an appointment? Any thoughts? I've never had strep before so any feedback is helpful for me. Thanks.