Hm, bumping my person in charge?
(I don't think its a mild concussion any, but im not entirely sure... xD)
Answers: Check your eyes if they dialate or not in the mirror. If they don't, after give your mouth a high-speed check, see if your mouth is bleeding anywhere. You might wanna go to a doctor if you want though. Remember don't sleep next to a concussion.
..i would probably see a doctor about that, but it depends on where on earth you bumped your head.
The blood probably come from your gum or inner lip... but you should check if your eyes are dilated or not in the pale if they are that usually indicates something may be wrong or if your speech is slurred.
If they aren't dilated then you most probable escaped any serious injury but to make sure you may want to keep hold of a eye out if any symptoms of concussion appear like a nausea, dizziness, or confusion. And see a doctor if they do.
probably a freak disaster, but maybe you wanna run check it out at the doctor. it's not good to cart a chance resembling that with such an out of the ordinary coincedence.