Thanks for your query.You had a injury to the forehead which is followed by a swelling and redness
of the eye.This is due to a transient bleeding in sub conjuntival plain.called as echimosis.Since you do not have other symptoms related to head injury
You may not worry at all.This hemorrhage will get absorbed off its own in a weeks time. In the mean while take Antibiotic like Ampicillin
500 mg along with anti inflammatory drug like Tab Diclofenac
50 mg twice daily .