Can you tell me if i get the last dose of my pre exposure rabies vaccine ten days late, what will that mean?

It's fine: You still will build perfectly good immunity. As long as it's pre-exposure and you complete the entire series, each individual vaccine does not need to be on the exact date.

Not much.: The ideal schedule is 1st dose then second dose 7 days later and third dose 21 to 28 days later. So there is some variability in the last dose. If you are 31 days after the start (10 days late with the last dose) there is likely not much effect. One option if you are worried about this, you can check your titer to the vaccine in the next 6 months to ensure you have developed adequate antibody.