Coughing up bloody phlegm

Hi all, over the past couple of months I’ve developed sinus congestion and bad postnasal drip. I saw an ENT (before I started coughing up blood). He ordered a CT scan. I was told I had mild nasal thickening, deviated septum and bone spur but nothing that required surgery so they didn’t want to see me again. I couldn’t get another appt to ask about why am coughing up blood. I was referred to an allergist but can’t be seen until the middle of January. I was able to get a chest CT which came back clear.
My doctors aren’t overly concerned but this doesn’t seem good. I recently had a bunch of dental work which included a root canal over month ago. I have a follow up with the dentist since the tooth is still sensitive and I have a small bump on my jaw from where it was done. I don’t know if that could be related.
My throat is always a little sore and I have been fighting viral infections since contracted Lyme over three years ago. I’ve never had anything like this happen before. It’s the latest development of so many ongoing symptoms that my doctor doesn’t know what to do with.
Thanks for any input and sorry about the gross picture.