My kitten is 5 months old on the 12th Nov. She has recently been peeing in this one corner of the house about a metre away from her litter tray. She knows she is doing it as just now we cleaned her tray out and she peed in the corner of the room. She is litter trained, she has been perfect since I got her. I did read that she could be in heat but I don't know what age they can. She is getting neuted on the 1st Dec.

What I have been doing is putting her nose in the pee and putting her in the litter tray for her to understand.

Any other suggestions

Cats are not really animals you can "give a conscience" to by rubbing their nose in the wrong.

I would say if you catch her peeing where she shouldn't, keep a small water gun or houseplant sprayer handy.

Peeing on the wall near a litter pan is a very common behavior... unfortunately. If you can, move the litter pan to some place where the pee cannot soak in (tiled surfaces) or you might have to resort to that sticky-backed shelf liner or some sort of sturdy plastic or vinyl film to protect your wallpaper. You also may wish to try a litter pan with a dome (make sure it is large enough and ventilated).

Talk to your vet when you take her in to get fixed, they might have specific product suggestions for you to protect your walls and carpet.