You can buy doggy pants, i bought ours from Mikki a few years ago.
Saying that none of our 3 girls bled much on their 1st season.
Betsy may become more cuddly, sleepy, clingy just before the season & for the 1st few days of her season. Her 'lady area' will swell before too.
I have noticed with Nina & Jo Jo that they don't always feel too good for the 1st few days either & wonder if they get tummy ache
they all tend to sleep more than usual at this time too.
If you are going to be taking her out at all during this time, i would keep her on lead at all times & stay in a quiet area where there isn't much likelihood of seeing other dogs. I don't usually walk mine in the middle of the season but do quiet lead walks at the start & end of their season's.
The average season lasts 3 weeks, although this can vary. My 3 are between 18 days & 24 days.
I am sure little Betsy will be fine, bless her.