I've taught K-8 and loved them all, although I don't ever want to teach K-1 again.
I taught 2nd and 3rd grade for many years; they were great. I thought 5th grade was great, too.
I've been teaching 6th - 8th for a few years now, and love different things about them.
It's true that middle schoolers, 7th grade in particular, can be tough. To be successful with them, the teacher has to be well versed in what to expect from them developmentally, and to love them anyway, lol.
To be honest, I like teaching all those grades so much, I sometimes wish I could take a 2nd grade class all the way through 8th. Not the best for them, perhaps, but I'd love it.
If you aren't comfortable spending every day with adolescents, and dealing with adolescent angst and issues, it's fine to explore your other options. Be aware that, while generally elementary children are more biddable, they don't all love to learn or love the teacher, either.
They have their own challenges. Check them out, and see which challenges you feel most comfortable with!