If all looks normal from a video / observation point of view you may want to have someone film you as you utilise different cues to reduce the heavy foot contact you are reporting. there are a number of different cues you can use as there is no uniform cue for every indivdual. From here you will be able to see if cues alone can change your foot contact. If you have no success from here then you can start working on specific exercises to improve foot contact.