It sounds very much like a strain or sprain pain to me. If you could get a wrist support (you know the ones with a little splint in to keep the wrist straight) it would undoubtedly help, or indeed a supporting bandage.
Non prescription pain killers may not be strong enough if it is a sprain so I would suggest you seeing your GP to get something stronger. He/she may consider sending you for an x-ray.
Just a couple of safety checks you might like to do.....Feel for your radial pulse. It is on the thumb side of the inner wrist. feel for it with your fingers never your thumb as the thumb has a pulse of its own and could give you a false reading. You don't need to count, just make sure the pulse is present
Also especially if there is any swelling involved, check that the fingers aren't blue. Pinch a finger or thumb nail and then let it go When you release the pressure you should see the pink colour return to the nail immediately. if it does not or if there is a delay and especially if there is also no pulse present, go to you nearest A&E/ER.
I am not trying to frighten you, I do not think for one minute anything like that will happen but it is always good to know signs to look out for.
I hope this has helped and I hope your wrist feels much better soon.
P.S. Please may I ask that if you are happy with my answer, could you be kind enough to click the accept button? it is just that although you have already made you deposit, unless an answer is accepted we do not get out portion of your payment. Thank you so much.