Managerial decision-making is a relatively big problem that people in this field encounter in this position every day. Because you have an employee underneath, you must have a fixed word and in many cases make a choice. This is quite stresmatically and mentally demanding, because you can always wash in your head, whether it was a good choice, if you should not choose rather the second variant and so on. But don't despair, it's difficult, but managerial work is worth it. Therefore, learn to live with the fact that you have a very great responsibility and that you will get every moment to the situation, when the next development will depend only on you.
In order to make a good decision that will be good not only for you, but for your entire department and business, you have to trust. You must be confident and be 100% confident that the choice you made was just right. It wouldn't work without it, but you'd be mired in the idea of what it would be like if you had done that differently.