How common is it for submitted papers to have minor errors? I am going to submit a paper in these days. I dedicated to it a lot of time, and a lot of effort to check that all the theoretical results in it are correct. Anyway, I am still afraid of having written something wrong without even realizing it, as the deadline is very sharp.

So my question is: how common is in the academia to find submitted papers with minor errors? If there is a minor error that is not invalidating the results, will the paper be rejected, even if the content is considered interesting?
That's what peer review is there for: to tell the author about the minor, but correctable mistakes in the paper. 

The way I see it is that, of course, I spend a lot of time writing my papers and making sure that everything is correct. But pragmatically, you will have to come to terms with the fact that no paper will ever be perfect. There comes a point where you just have to take the plunge, submit it, and hope for the best.