Even though I have never watched Dr. Who, I can tell it's a reference from that show (hopefully!). I am not an artist whatsoever, so many things amaze me when it comes to drawings. But this is great. I especially love how shocked (especially Time Turner's "What is this-I don't even" face) everyone looks except Derpy, with her happy-go-lucky attitude. This picture might put me into a position to watch it if my Whovian friend don't force me to first. It is very realistic and well done, and I can tell tell you take pride in your work. Keep drawing!
What I like the most is that the current Mayor of Ponyville used to be an assistant of The Doctor. I've seen plenty of "other" assistants in different pictures and fanfction: Derpy, Twilight, Trixie... but the current Mayor as an assistant of a previous Doctor? That is just SO original. And it FITS!
Here's what I think is going on. Dinky jumped out of the TARDIS while in flight and ended up being caught by the past doctor, who was traveling with Mayor Mare. Dinky told him where she came from, and here they are in the future. Derpy's happy to have her daughter back. The Past Doctor is saying, "Am I really so irresponsible that I allow children on the TARDIS in the future? Honestly!" The Past Mayor is shocked at seeing herself. And the Doctor is feeling quite embarrassed because he knew this would happen.
In this pic the Doctor meets himself from the past, when he used to travel with the Ivory Scroll, before she was the Mayor of Ponyville, and in the present, when he travels with Derpy, who's daughter is Dinky Hooves.
you should of done that one pony who was supposedly the 5th doctor so it could be like immitating the episode of Doctor Who: Time Crash because on that episode the 10th and the 5th interacted and worked together