Is it acceptable to use a mix of object oriented style with procedural style in coding PHP?

So before I always used to use procedural style to code php, such as:

mysqli_connect

or

mysqli_prepare

And now I accidentally began to mix it all up and I would do something like:

mysqli_connect();

which is procedural style, and then the next command:

$mysqli->prepare();

which is object oriented style.

My code still works, but if I look at php.net whenever it shows examples the entire example is either object oriented or procedural. So I am asking if its ok for me to use object and procedural php code at the same time. Thank you in advance!