Hi, My 8 Month Old Baby Girl Just Hit The

Hi, my 8 month old baby girl just hit the back of her head on a sharp corner and she started bleeding. I was sanitizing the tub, getting her ready for her bath, when no more than 12 inches away from me I seen her falling back. I reached for her shirt and managed to break her fall, but she did end up getting a small gash (size of the tip of a q-tip). It bled in a pea size amount as I applied pressure. How long should I wait before putting her to sleep or should I take her to the ER?