I cut my thumb across the top pretty deeply (slipped with a box knife). Stopped bleeding after about 24 hours but now skin over knuckle has no feeling at all and rest of thumb tingles. Also hurts when I bend it but I assume that is the skin just stretching. Is this OK or have I done some nerve damage

It is impossible for anyone online to examine your thumb and diagnose whether you experienced nerve damage when you cut it. The symptoms you describe could mean nerve damage or it could signal an infection setting in. I hope you get a doctor to look at it soon.

Depending how far up you might lose that portion you cut. Normally it should have been isolated and not moved at all through use of a splint and protection. Also the tingling could be a sign of infection. You really need to let a doctor see it to make sure.

Go to the doctor. If it bled for 24 hours, it was a deep, serious, cut.

Don't take any chances with your health like this.

You will not get the proper answer here. No one can see the wound but you. Go.

I too have just sliced the tip of my thumb clean off with a folding picket knife, funnely enough while sharpening it. ( I guess its sharp enough ) I've taken about 5mm off the outer corner of the thumb tip, going threw the nail and all like it wasn't even there the fact that it was done with a sharp blade is an advantage. I've been a mamber of the emergency services were I live for over 10 years and have done many advanced first aid couses. Regardless of this face I still wouldn't take the chance, a fingure you can do without a fingure, but a thumb lost to infection and you will be asking your friends to open your beer bottles for the rest of your life. Have a think about that fact and all the other things you need your thumb for, and ask yourself is it really worth it for a trip to a doctor? If he says all good then at least you know, and if not he will be able to treat it before it gets too bad.

Aussie Bob