Gilly didn't have her heat until she was about 18 months anyways, and we waited three months after that to get her spayed. I was stressed too! The mess itself (blood drops and stinky butt dog) didn't bother me at all. But I actually had nightmares (during her heat cycle) that somehow when I wasn't looking she got out, or some boy got in. I think the stress for me came from the knowledge that if somehow something DID happen, our contract says the breeder can take her away from us and fine us several thousand dollars (I think this is a fair stipulation, but it sure is scary!) Plus taking her out to pee/poop on a leash in our own yard, and all the regimented on-leash walks were hard for Gilly who loves her offleash adventure walks - she gets out so much more energy which makes all of us happier.
I am happy with our decision to wait until after her first heat cycle, but I'm also happy it's not in our contract to wait until she is 2+ years or until more heat cycles have passed. Personally, I feel like I'm not a breeder, i'm not an expert, and it's a lot of work, so while i DID seriously consider Gilly's health I also needed to consider what was reasonable for me and our family.