Trigger thumb?:Sounds like (in this case ). Often happens from overuse. Best to see a , who can give you a steroid injection. If it keeps coming back, you should consider surgery (which is a simple procedure and very effective).
Mashed your thumb?:Sounds like a minor injury. Pain should gradually subside. Dark color in nail will slowly be carried to the edge of the nail and shed off.
You see, these things don’t matter to me anymore. In fact, I’m pretty sure that what I read as horror on people’s faces as a child, was actually delight. Yes, my thumbs are delightful.