The other night I noticed a sore throat coming on. I had a throat sweet and ignored this. The next morning I could feel phlegm in my throat, noticing this sensation I coughed it up over the sink. I noticed some blood in it. The phlegm in my throat lasted for around two days. Since the phlegm in my throat has cleared, I've developed a cold. Was this just a symptom of me developing Flu or cold this be something more serious such as HIV Stage one?