Often a dentist is the best person to look at your tongue as they seem to be a lot more aware of problems in the mouth in general. I get a lot of really big blood blisters on the side of my tongue which give me an awful lot of problems with eating and are also very painful. My GP wasn't very helpful at all and just said they are caused by trauma and not to worry. When I saw my dentist she advised me to get some Arnica homeopathic tablets as she said they are very good for that kind of thing. From what you say about your symptoms it really does sound like anxiety because if this feeling goes away when you are occupied with other things then it really can't be anything else