Conditions valid for plagiarism and dishonesty
Once you have your degree, your university probably can't do anything, and would not bother with something like this anyway. If it were a thesis, it might be different, but not just one assignment. I give this information as the person who handles plagiarism, etc., in my department.

Anyway, the important thing is that you did not submit someone else's work. Getting help is fine as long as you submit your own work, and it sounds as if this is what happened.