Kitten has stuffy nose for the past 2 months

I’ve bought a new kitten 2 months ago. She was 3 months at the time, and is 5 months now.

The day I brought her home, I noticed she had a runny/stuffy nose and one eye was quite watery. I brought her to the vet, and got some eye drops on natural basis. After 1 week, I brought her to the vet again, as the drops didn’t seem to work and the second eye was starting to get watery as well. I got some antibiotic eye drops, and they worked really well.

However, her runny/stuffy nose turned into a stuffy nose only. Most of the time when breathing, she makes "noise" because of the stuffy nose. It sometimes even reminds me of a small pig.
She doesn’t seem to have a hard time breathing at all, but still, I reckon this isn’t normal and I’m somewhat worried.
She often sits in the bathroom when I take showers, but the steam didn’t seem to help her (maybe it does temporarily and I just didn’t notice).

Has anyone had something similar and might know what I need to do to help her get rid of the stuffy nose?
The next step would be to bring her to a vet. I didn’t do that yet, because she generally doesn’t seem to have a hard time breathing, and she also eats, plays and sleeps just fine. But then again, cats seem to be known for hiding pain.

If it helps at all, I could make a recording of her breathing.

Thanks.