Hello everyone I'm new!

Okay, so I've probably had my bp for about a good 4 months now, and she has been really good. A while ago, I took her to the vet because she was drooling and she apparently had snake allergies? Or well I at least caught her early signs of a RI. Since then, she's been fine except that right now for this past week, she's been out and about for hours at a time even at night. She also is always trying to reach the top of the cage and stays still (like if she's concentrating on something) and then comes back down in her tank and then does it again. Lastly, today I went to get her out of her tank to feed her and I picked up this basket I have in her tank where she lays under. When I went to touch her back like I always do before I grab her, she became unusually very frightened, so I backed my hand out of the tank. As I slowly started moving the top of the tanks cage part to close it, she rose up and snapped at it very fast. It was like random aggression and she's never done that before. After a couple of minutes I was able to get her out of her tank, and she was totally normal so I fed her. I've read things before saying she could be stressed, but i don't know why she would be. I thought she was maybe just hungry because I always feed her one mouse every week, but she has grown a lot so I gave her two instead because of the whole "exploring/stress" thing. Also, I've checked for mites and I don't think I see any but she does always rub her face on the tank. I would like to rule that out but I don't know that much because she's my first snake. :// She's also been drinking a lot of water.
Please help I'll take any response! Thanks so much -bri