Beagle having accidents following surgery and starting on doxycycline

Hi everybody,

My 9ish year old female beagle, Matilda, had surgery yesterday to remove a suspicious lump on her stomach (she has a history of tumors) and a good chunk of her breast tissue (because of that history and this new lump).

(The vet didn't give me any painkillers for her, and like a dummy I forgot to ask about it...)

She also got tested for ehrlichia and the test came back positive (yikes), so last night I started her on doxycylcine.

Last night, she seemed fine. No weird behavior or anything - a bit slower going up/down the stairs to the apartment, but that was it.

But today, she has had several accidents (pee, no poop) in my kitchen. She never does that, so I'm a little concerned.

I don't know if it's because she's in pain from the surgery, or if it's a side effect of the doxycylcine.

But:
Normally, she's really obvious when she's in pain - she shakes, and whimpers, and cuddles up as close to me as she can get, and she's not doing any of that now.

And I can't find anything online about that med causing more frequent urination, but maybe one of you has experienced this?

(I've been trying to call my vet for hours now, but they have been having major phone trouble for like 2 weeks so I keep getting disconnected, or I connect but then they can't hear me or I can't hear them. So I'm going to keep trying, but I wanted to just put this out there and see if anyone has some thoughts)

Does anyone know of anything I can do that can help her besides taking her outside more frequently for a while?