Yeah, the pet PvP queue is known to be … let’s call it “unreliable”. 
But 99.999% of people entering the queue are doing so with Level 25 pets, and so you won’t be matched against them. Waiting for someone to queue with Level 1s and 2s could truly be a loooooooooooooong wait!
(And when you do get a match with Level; 25s, you are likely to meet one of the sharks who has been damned to queue almost endlessly for the 5000 wins achievement.)
You can get your pets to higher levels more easily by matching against the Tamers, and there are other ways, like using Level 1s against BFA and Shadowlands World Quests, to earn Polished Pet Charm , with which you can buy Ultimate Battle-Training Stone, which boosts one pet instantly to Level 25.
If you do want to know more, or want a hand with anything, please do let me know. I am also available on both of the Pet Discords, where pet battlers and collectors congregate - and complain about pet drop rates!
I have a four-part guide here: