My Puget Sound Garter once extremely friendly and willing to be picked up has now become very skittish around me. She's started to slither away very quickly when I put my hand in her enclosure to have some "bonding time", and she's lunged at my hand a couple of times. Today has been the worst. I was able to pick her up at first and she started thrashing. She slithered out of my hand and onto the floor (i was kneeling down, so she didn't fall) and I ended up having to chase her around the garage. She also musked all over my hand for the first time.

What happened? She was fine a few weeks ago.