Hi there Notsportygirl,
You can do it! Just take your time and work up to the 35 miles. Riding a road bike will be much different then the one-speed vintage that you currently ride! I have major allergies and out here in California I am always in need of an inhaler! I just take my time and stop when I need to, to catch my breath. 35 miles is not that bad! If you average 10 miles an hour it should only take you about 3.5 hours.

Melody