New kitten sneezing and blocked nose

Hello I am a new member and have recently got a new kitten named Tabitha. She was unwanted and not very well looked after so I took her off their hands. She was underweight and had only been fed dry food before now, and I have noticed from day 1 she has been constantly sneezing and has a constant blocked nose that makes popping and whistling sounds when she's breathing and especially when sleeping. We are registered with the vet and due her first immunisation this coming week so will be asking for them to check but just wondering if there is anything I can do to help with her breathing in the mean time? Thank you

Bless you for rescuing this kitty and giving her a good home!  Sounds like she has a little upper respiratory infection or some allergies going on, similar to what we humans get.  A vaporizer will help ease the breathing.  If you don't have a vaporizer, you can steam her in the bathroom as many times a day as possible to help open up her nasal passages and get rid of the congestion in her nose.  Just get the shower good and steamy, then sit in the bathroom with her until the steam dissipates.  If the discharge is colored (yellow or greenish), then she's got some kind of infection going on.  Are her eyes running as well?

Thank you for your reply its very helpful. I dont have a vapourizer so I will definitely try the steamy bathroom she follows me everywhere so she would happily sit in the bathroom with me whilst I run the shower. There hasn't been any yellow/green discharge but her eyes keep getting a bit crusty in the corners that we have gently wiped away but not actually running or watery? Thanks again