Normal HR in an adult is between 60 and 100. If the doc took your pulse, you were probably just anxious enough to elevate it slighty up to 90. It's called "white coat syndrome". It's happened to me, and it's happened to some of my patients.
I wouldn't stress about it. Try checking your HR when you are sacked out on the couch, watching TV. I bet it'll be in the 60's, or lower.