I had turned 25 2 weeks prior to the birth of my twins And I had my third and last at age 29.
If anyone says you are young, tell them that no- are are at optimal age to be gestating TWO babies. Your body will handle it perfectly well (better than a teenager, and better than someone in their thirties or forties), and that for a high risk pregnancy you are at an excellent time in your life to be handling it.
Honestly- don't let anyone rain on your parade. It is very exciting news, and not every woman gets to hear that she is growing more than one baby, or tell other people and see their reactions. The reactions of others (the positive ones!) are the best part