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Yes, as the very act of seeing oneself is bound to impact in some way upon one's future actions, causing a bootstrap paradox. However, the paradox isn't of the universe-destroying type. In fact, characters have interacted with past versions of them selves several times, such as the Brigadier in "Mawdryn Undead", and Amy & Rory in "Space"/"Time". Oh, and we can't forget the Doctor in "The Three Doctors", "The Five Doctors", "The Two Doctors", "The Big Bang", and "The Day of the Doctor", along with a few others.

While people can look at past version of oneself without harm, multiple versions of the same object cannot touch (unless they are the Doctor). If they do, the Blinovitch Limitation Effect will occur, releasing a large amount of energy. ("Mawdryn Undead")

If past and future versions of the same individual interact, the memory of the event will be erased from the past version's mind until the future version has finished experiencing the event, to minimise the problems of a bootstrap paradox ("The Day of the Doctor").