I think you should give it a try, taking the advice to have drink a post-ride recovery drink, e.g., chocolate milk, within a half hour of the first ride, followed by a meal that incorporates both carbs and protein, lots of rest, healthy food, and stretching. I would further suggest doing at least two short, easy rides in betweeen.
In between now and then, work on building up your mileage volume. Do you ride both weekend days? I would use those back-to-back rides to get your body adapted to shorter recoveries. As a new rider myself, I have found that my body is pretty adaptive. It always balks a bit at each new challenge, but it doesn't take too long for it to get used to new stresses. I think you can do it without much problem with a little bit of training. And if you go slower on the second ride, who cares? Enjoy yourself anyway!
Good luck,
K-
Live with intention. Walk to the edge. Listen hard. Practice wellness. Play with abandon. Laugh. Choose with no regret. Continue to learn. Appreciate your friends. Do what you love. Live as if this is all there is.
--Mary Anne Radmacher