Ann
Moderator
Never having had a female, I have no idea what to expect when Willow does go into heat or how long it will last or how much trouble it will be to manage her through it. Certainly yard play will take the place of walks. I've always had boy dogs in large breeds and they were no problem to manage until they were neutered.
Glenn, girls are pretty easy, and you can certainly still take Willow for walks and out to play when she's in season. Just keep her away from boy dogs. Girls can have their first season any time after six months, although all of mine have been after 9 months and Flurry was 14 months old! So you never know. Be prepared with some "seasonal" panties (you can get some online--I buy Medium for Sheltie girls) and line them with pantyliners.
Some girls get moody but mine have never exhibited any unsual behavior. It's a good idea to have her spayed after her first season...your vet will tell you to wait two to three months after her season ends, that's so her uterus can return to normal. Heat seasons typically last 3 weeks...seems like forever!