Will becoming an egg donor affect my chances of having a child of my own in the future?

Not that we know ... As far as we know being an egg donor does not affect your future fertility potential. But 'just to be safe' as well as to reduce the chances of kids from the same donor having kids together, we limit each donor to no more than 6 egg donation cycles in her lifetime, across the us. As part of becoming a donor you will be tested to make sure you have normal or above-average egg supply / fertility.
Not likely. Most studies to date, along with anecdotal data and experience, show that fertility is not affected by egg donation.