Is it time for an oil change?

So I've read a ton of these posts and I know there will be a few smart arse answers but being a new rider with less then 4 months experience, I'd rather be ridiculed and get a valid answer somewhere in there than cause damage to my bike.

So I bought my z400 in May, did my first service at 1500kms. I started taking my wife out for rides with me as soon as I was legally allowed to. (In Canada e have to wait 90 days after obtaining our M1 class license to upgrade to the M2 which allows passengers) Fast forward 4500kms to now.

I've just broke 6k kms and approx 4k of those kms I have had a second rider, my wife and myself are below the 400lb recommended max weight but by only 50ish pounds. Should I do my oil change now or relatively soon because of the extra stress I'm putting on the engine due to having a rider on my pillion? Dose having a second rider actually cause extra stress on the engine or is that in my head.

I will be switching to the motul 7100 10w40 oil and either the hiflo303rc or the k&n filter. I'm aware of the recall issues with the k&n filter but I know betternthen to use the nut to put on the oil filter. All suggestions/recommendations are appreciated.

TLDR: Do I need to do oil changes sooner if I have a rider on my pillion and we're close to the bikes recommended max weight load?