How To Treat A Small Bump On The Head Caused Due To A Injury In An Infant?

My son is 7 months and fell off the bed while I went to get something in another room. When I heard a thump then a loud cry I ran in and saw him on the floor. I picked him up and comforted him right away, he stopped crying almost within seconds. I examined his head and body (hands, arm, legs and neck) to make sure nothing was broken...all seemed fine. We spit up a little formula but that was all. After holding him for a few minutes he was babbling, smiling and laughing per usual. It was feeding time and I began to feed him his rice cereal and he ate well and drank some formula. I observed him for the next 2-3 hours and he didn t vomit or seemed out of sorts and started playing normal as usual. An hour ago I noticed on the front top part of his head a small tender bump, not big just a bit swollen. So I took a cold pack and placed it on the bump for a few minutes then removed it. He fell asleep for his nap and seems fine. Should I be worried about his overall condition?