I just got 3 spirits headless horseman grim reaper and draugr and bound them to my spirit and im kinda worried now that they will be bound to someone else same name birth date has that ever happened and should i be worried?

I can say with 100% certainty that has never happened. There may be thousands of people who share the same name and birthday as you, but there's only one you with your unique energy signature, and it's your energy that the spirits are being bound to.