Puppy Biting Hard Help

We are having issues with puppy biting. We have a 6 month old 6 lb Chihuahua/Dachshund/possibly Toy Fox Terrier puppy that we rescued a little over a month ago. She was not a biter when we got her.. But we had lots of issues with my senior Golden Retriever not getting along with her & her deciding she wanted to be aggressive toward my husband. Luckily, those situations have improved a lot.

But during that time she had to spend quite a bit of time in a baby play yard & I think she began to associate hands with going in the pen because that's when the biting started. She was also getting frustrated having to be in there so much even though we took turns locking her & my other dog up. I got a gate attachment for the play yard a few weeks ago so I rarely have to pick her up now unless I am putting her in her crate at night (she won't go in there willingly but does sleep through the night) or going in our van. She will go into her play yard herself with treat incentives. And now that things have improved with my other dog/husband, she gets a ton more free time out of the pen so she is less frustrated.

But she bites and she bites HARD. Today she started biting my finger tips with a lot of pressure & didn't want to let go. I try redirecting to toys or bones (she has a ton of options) but most of the time she'll just move around it & right back to biting me. She doesn't growl while she's doing it so it could just be puppy biting but it seems to be getting worse. She does the same to my husband & kids. It's mostly when we go to pet her (even if she comes & rubs up on us) but sometimes she just comes over to us when we are minding our own business and starts biting… Hands, toes, arms, thighs. When she goes for my wrist I tell my husband shes going for my veins to bleed me out. 🤣 I have tried helping but it gets her excited & she bites more.

She did just lose a tooth the other day. And also we had a trainer come to our home to help with our other issues & I did mention the biting.. She said it was normal. She didn't see the worst of it while she was here. I can't afford anymore private sessions but we are in puppy obedience classes for 4 more weeks with the same trainer that came to our house (puppy doesnt bite me there lol).

I would love any advice anyone has to help decrease the biting!