Being scared is absolutely normal. At the end of the day it does not matter if you have one or three, it is not the quantity that matters, but the method, and that - as with anything - must be the same, either for one, or for three kids. I don't think three is that much more work in terms of disciplining, by the time you have the third, you will have graduated at the parenting university, haha...
Disciplining tots and teens seems to be the same, at least for me, it's fun to teach teens, I love it.. Dignity, kindness, being firm but open to explain. I was never a fan of time-outs, it does not teach anything, just deters. I am missing the positive bit in that tool. What has worked for us is being consistent, explain explain explain, and - oh bless those - natural consequences.
Ie - a child screams to get something, there is no way she gets it, we leave the store. A child hits a playdate (mommy, ...), playdate leaves. A toy flies on the wall, a toy gets some good time with mommy who is so sorry the toy got hurt and pets it and puts it away to safety for a while (loooong while). Some food flies on the floor, if that is repeated (I don't like having a hungry tot around), food goes back to the fridge. Stomping and other "fresh" attitudes don't get tolerated, if we plan a fun outing, we stay in until the unwanted behavior calms down. We say no, thank you, yes, please, hello, good bye, we shake hands, we wave good bye and are civil to people.
It was a pain the butt to be consistent with these, especially if one has a non verbal kid for a long time, frustrated, learning too much at the same time, the terrible twos are challenging..But it worked. You have to get on the level of the child, speak calmly, eyes on the same level as hers, and explain what happens if the bad behavior keeps going. Keep your emotions out of it. You have to get off your butt and not yell comands to your child from a distance, wondering why your tot is uninterested. Physical presence and talk works wonders, light touch on the shoulder reminds her we are in it together. Same as after a talk, if the offense was not too bad, it's good to hug or check "now we are good?", my daughter likes that. Giving plenty of choices for them to play with, when things are not so important, works really well too, keeps them happy they do have control over their lives at least a bit (activities, food, clothes, friends, places to go, toys...). If one abuses the "no", hits or over uses restrictive socially isolating methods like time-outs, that's pretty much the end stop and nowhere from there.
I really thought about different ways, I thought about why we as parents discipline and this always made the best sense to me, kids won't have the cop/parents around all the time to reinforce the threat of being hit or put into a time out. We need to teach them how to make wise choices on their own, without us being too controlling, they should want to abstain from being bad not because they will be put into prison if they do something bad but because the consequences that their negative behavior might have on other people.
I second the cheerful, creative and loving attitude of positive parenting, rather than a patronising power game "I am the parent, I always know better". Big bull.
Kodokan, I love your input.