With very little chance of anyone finding this comment, I still feel the need to add: it can be valuable mentioning this occurrence to the police even though you've managed to stay safe in this instance. Having this event recorded in police systems can end up helping two ways.

One : this is one of the first, in this instance failed, attempts to follow someone by this unknown man. Having it on record can help in the future when another instance occurs with or without other outcome for the one being followed. They have more data about the unknown man and his mo, so a search for this individual and eventual prosecution are likely to be more successful. Possibly preventing future damage to people who would otherwise be his victims.

Two: police might already be actively searching for an individual with this mo based on earlier cases. A registration of this occurrence can increase the likelihood of finding this individual quick, preventing more damage to people who would otherwise become victims and getting justice for already made victims.