Not really. That would be "Miałam/miałem coś do zrobienia" which changes the emphasis. For example:
- Why didn't you call me yesterday? (Dlaczego wczoraj do mnie nie zadzwoniłaś/-łeś?)
- Sorry, I had something to do. (Przepraszam, miałam/-łem coś do zrobienia.)
is different from:
- Couldn't you do this later? (Nie mogłeś/-łaś tego zrobić później?)
- No, I really had to do it now. (Nie, naprawdę musiałam/-łem to zrobić teraz.)
In the first case, the emphasis is that there was something you had to do and in the second case, the emphasis is on the fact that you really HAD to do it.
I don't think that's correct, at least not in this context.
If you're trying to replace "doing something" with "making something", then that won't work in English in general - they're not interchangeable like this.
However, if you're saying "I had to make something" because you're creative and you constantly want to create something, then that would be a correct sentence (in English), but then the Polish translation would have to be "Musiałam/musiałem coś stworzyć". The word "stworzyć" basically means "to create" or "to make" in the context of a creative process.