I bent/stubbed (not sure) my big toe and applied ice because it throbbed. although i can bend it, the top area around and just under the nailbed hurts when i touch it so it hurts to walk. what have i done to it and what should i do? thanks?

It is a common injury, you had a contusion to your big toe. Pain should get better in the next day, use ice pack and/or Ibuprofen 200 mg x 2 q6 hrs as needed for pain. If the contusion is hard enough, you may see the change in nail bed color due to subungual bleeding.

You bled under the nail. You may lose the nail.Its probably too late to drain it. I suggest you see a Podiatrist.