
Hi,
A good book to have is "the book of the bitch " it gives you all the information you need about dogs cycles .(available on amazon)
Some bitches can have a "show" right through some only on the first 5 days or so nothing unusual in that.
Make sure you make a note of her first day and count 21 days for the cycle whether having a show or not
also some bitches seasons can last longer more into 4wks so be careful I usually add on a few more days to be safe.
If you turn her over and take a look at the vulva it will be swollen a good sign that she is definitely in season.
remember to mark on your calendar 6m to give you some idea when she is next due.
HTH
Roni