A lot of excellent responses below. As a parent of a teenager, I just want to add one aspect to the advice you've already received: When she starts school (even if she's in K now), one truly great way to start to find peace with your own imperfections and to let go of control is to get to know other parents of her classmates. By making some good friends among other moms of my child's peers, I found that I wasn't alone in feeling like "I should have this down by now and I don't." You are getting some of that via this site but I think it's important to have some friends and acquaintances who are your own peers you know in person, with whom you can share stories about your kids and your days and hear about theirs. Sure, there will be some moms who are Just Perfect, but most will be like you -- I want the best for my kid, but then this happened....Sharing those things really puts your child and your relationship into perspective.
If your daughter is in preschool, get to know some of the other parents there; if in K, it's especially useful to get to know parents, because you likely will be around those families for years to come, and if you can find some real, adult friends among them, that's going to help you. Just having kids in the same grade does not make two parents into friends, but if you find some moms with whom you have other things in common, it can help to say to them what you said to us here.
One other thing, regarding perfection and control: Sit down and consider well whether you also seek out perfection and control in other aspects of your life-- not just with your child but in other regards. Does the house have to be "just so" or you get into a funk or feel a bit angry that it's not perfect? Do you expect yourself to make things perfect for your husband so things are always ideal for him when he walks through the door? Are there other areas (work, adult friendships, relationships with your parents/siblings, your own appearance, etc.) where you find if hard to adapt to any changes, and/or you "lose it" if you lack control? I would really consider if your need for control with your daughter is part of a larger pattern that could benefit from some counseling. If you maintain an "I need control and perfection or I lose it" personality as your child gets older, whether you mean to or not, you will drive a wedge between yourself and her, and possibly between yourself and others in your life. Just something to think about objectively.
You already DO recognize that a need for control and difficulty adapting to change are problems for you -- that recognition is very, very positive and important so credit yourself for that. Now, you need to get beyond recognizing the problems and working to get past them, and that may take someone who is objective and professional. It never hurts to just talk through things with someone--a counselor for the big picture stuff, and parent friends for the day to day "I'm in a funk because..." stuff.