Guilty from exposing baby to xray radiation

As a first time parent, a lot of things we were not sure about. Recently we felt a dent at the back of baby head. Baby was only 1 mth old. He was fine and was drinking normally. Decided to head to A&E to consult whether is it normal. A skull xray was ordered. Was abit reluctant to do as we felt it wasn't smth serious but we still went ahead just in case. Result came out normal. Was then referred to a specialist for follow up and was told that the dent i felt was normal for him. Asked if the xray was neccessary, she said strictly speaking no, but becasue we went to A&E, they ordered xray to rule out something serious. Perhaps, they were also not specialised in this area. Until today, I blame and question myself if the visit was even necessary and am i being overly paranoid over the dent. Also, as a first time parent, we were not sure where to bring baby when we have concerns. Felt that if we had brought him to a head specialist, baby could have avoided the test and thus being exposed to radiation. Our love for him ended exposing him to radiation esp when he is so small as there is always an increased risk of cancer from radiation. Felt really down & guilty