Painful lump in chest
I'm a 22 year old male and there's a lump in my chest which has suddenly become very painful. I'm going to be honest, there has been a lump there for the past 6 or 7 years, but it has never ever cause me any pain before. I'll try to describe it in as much detail as possible so that I can get your thoughts on it.
Like I said, it appeared 6 or 7 years ago, but was never painful. It's located on my sternum, more or less directly in the middle of my chest. It is a firm lump, but I've always been able to move it around a bit. A few hours before I went out last Friday night I noticed that it was suddenly hurting me, so I lifted up my shirt and poked at it and noticed that it had suddenly grown to twice the size it was before and was painful when I touched it. I disregarded it and told myself it would probably stop hurting in a day or two, but it hasn't. If anything the pain has probably gotten worse. Last night I realised it was hurting even when I walked. If I try to pull my arms back behind my back it is extremely painful, kind of like it's being pulled on or something. It's more or less a round shape, about 1 inch wide and 1 inch long.
I'm going to call up my local GP tomorrow but it will probably be next week or so before I will be able to get an appointment.
Any thoughts on what it could be are appreciated. I am one of those people that thinks "it will sort itself out." but this actually has me worried, so it is something I am definitely going to get checked out.