It can be so tough to get an answer
for sure when it comes to reverse sneezing (RS). How old is Bella again? Usually if they have RS, it starts sometime within the first 1-1.5 years, but it can start later too. Wylie kind of outgrew it.
Marcel does it (ever since his neuter, where I think they damaged his trachea) and it has no real pattern in terms of activity. Sometimes, it sounds just like a normal RS episode. Other times, it sounds "wet" - and those are the scarier events, for him and me both. It's those times where I wonder if he's headed toward CT. But not sure.
To me, her episodes do rather sound like RS - but the runny nose is kind of concerning. I think this happens to Marcel during the bad ones too though - and I think all of the pressure in the upper area causes fluid to push up and out the nose. I always make him kiss me to break up the event.
Since Bella's issues did just start after associating w/ another "snorting" dog, it does make me wonder if she caught something. Hopefully, the vet can easily rule this out. Another thing to think about is whether you've introduced any new chemicals or foods - sometimes allergies can make the events more frequent. I always keep an eye on pollen.com to see if his episodes are related to particulates too.
I know how you feel - RS is so scary to watch and I just hate it. I do hope it is just a cold and that your Bella is feeling better soon! HUGS.