Never had it before and I think mine is/was definitely infected.
I was so scared I rang 111 on Saturday and I was given a Dr's appointment, but I declined to go and got a nurse/practioner to ring me instead. She never suggested saliva gland, but I think I may have steered her in the wrong direction.
I got a sickly sore throat on one side last Tuesday. Was concerned as I know that's a symptom of CV19, so I was quite anxious about it. That lasted into Wednesday morning then disappeared. Then it felt like my ear was hurting so I put some ear drops in. All week I had this uncomfortable feeling on that side of my face and painful to eat. Then Friday evening it was really sore and warm to the touch.
Saturday morning I woke up and I looked like a chipmunk on one side. That really scared me so I rang 111 and eventually by the time they called me back it had started to go down. Obviously I talked about the throat and the ear, not thinking anything else. She said it was good sign as it shows your immune system is fighting back when the glands are up. All week that side of my face has felt odd and in the corner of my mouth it felt like a cold sore was coming so I kept putting Zovirax on it , but nothing appeared.
It was only when you I found your thread it realised - saliva gland. The people who responded to you nailed it with their descriptions and of course the salty fluid thing. The first time that happened the swelling went down significantly and when I press or massage it, I also get the salty fluid in the mouth.
Mine is a lot better, still a slight swelling, but much, much smaller and less tenderness and pain. No more issues when eating either. One day I didn't eat at all, just drank green tea all day.
So fingers crossed on the mend.