Hi there, in your esophagus there are many tiny blood vessels, and if you have suffered from acid reflux, any liver problems, the blood vessels can suffer damage and you can start to bleed from the burst vessels. This is not something to ignore. Are there any other symptoms you've had? Abdominal pain? Heavy metal toxicity can cause many issues and damage in the body, have you had any metal testing, like for high iron, copper...? These are not standard blood tests and you need to ask about geting screening tests for iron overload. Look it up and see what storing excess iron and metals in your body can do to organs, tissues etc.
Hope you get some answers soon.
I understand anxiety and health problems can be a very worrisome combination. It can't hurt to visityour family doctor. The first thing I would try to do is spit - see if there is blood in the spit. Cough up a little mucous (if possible) and see if blood is present. I'd also try flossing and see if your gum lines are the source of the blood. I'd be curious to know where the sensation is, and perhaps blotting that area with a paper towel or cotton swab would determine if that's the source of the blood (assuming it's not so far back in your mouth that it could cause you to choke).
There are many reasons that you could be experiencing this - and one common cause is a respiratory infection - so, chances are - you'll have to visit a doctor anyway.
Stay calm and just take the proper steps to have it taken care of, I'm sure it'll work out ok.