2yr old with bruise/egg bump middle forehead from fall. no passing out, vomiting etc & seems fine. should i worry? how long to go away? thanks.

Likely no worries: Keep checking for new symptoms, there is likely a blood collection under the skin, the forehead is pretty strong, if your child is happy, playful, eating, sleeping well, there is nothing to worry about. This can take up to 2 weeks to go away. Applying ice within the first few minutes after the fall can lessen the size of the bump. If more than 5 minutes has passed ice will not work.