Stuffy noseand congestion

My cat just recently started having a couple sneezing fits. I figured it was just allergies. It stopped for a few weeks. Now, she is really congested with a stuffy nose out of no where! -No watery eyes or any mucus that is green/yellow and she is acting 100% herself and eating. I have a humidifier going an got her some over the counter drops. The Pet Wellbeing Throat Gold we tried for two days first, no relief. After that we tried HomeoPet nose relief. Yesterday was the first day we started it along with today. She now is starting to sound a littlIe squeaky when she breathes. She is still breathing out of her nose, one side is blocked. Today, I tried a saline drop in her nose and had her in the bathroom with me while I showered for more humidity. I bought lysine chews that just came from amazon today that I will be giving her. I can't afford a vet at this moment in time as I'm out of work due to a broken leg. Does anyone have any suggestions or over the counter meds to try?! I will appreciate any advice!! Also, nothing has changed, food, litter, everything is still the same.

ALSO!! I want to add that I do have one other cat that is perfectly fine. Zero issues with that cat. The affected cat is about 6 years old. Zero mucus, no tears. She weighs 10lbs. Both cats are 100% indoor cats that barely leave my bed all day (haha).

Hello - when only one side of the nose is blocked, I would worry about physical blockages, for example tumours or polyps, which I would not expect Lysine to shift.  Fungal disease can be another strong possibility.  I do not know the contents of this supplement or the basis on which it being given, but as a scientifically-based vet, I would want to rule out some of the more concerning possibilities first and this may necesitate stronger, more specific medication and / or a radiograph of the nose, so I would consider seeking scientific veterinary advice as soon as you are able to.

(Lysine apparently has shown to help to some extent in some cases of cat 'flu - however, at the moment, you sound to be a long way from even knowing whether cat 'flu is a possibility for your cat.  Even if it is, I suspect that relatively few cases of cat flu are actually cured by Lysine drops, so would strongly advise against relying on it and would encourage you to see a vet.  I don't know where abouts you are but in my experience, shelter vets are often very experienced with respiratory cases).

I hear that this may not be the most useful answer, and wish you all the best from here.  Once they have heard the history, your vet may be able to advise you whether steam therapy might be appropriate.