In heat or something else?

Question
I have a 14 month old female boxer. I got her from a breeder when she was 10 months old. The breeder said she could have had a heat but she wasn't sure. Is there any way you might be able to tell? Also yesterday she seemed more swollen than usual but not a lot and last night and today I noticed a few drips of dark red/brownish discharge after she comes in from going potty. Do you think she may be slowly coming into heat or could the brownish discharge and swelling be from something else. If she is in heat will the swelling increase as she gets near time to breed or do they usually swell quickly over a night or two? Sorry for so many question but if she is in heat I want to know cause I don't want her to get pregnant yet. Thanks

Answer
KC
Yes she is definitely in heat.  She will get more swollen and she ovulates and becomes ready to receive a male.  She is not slowly coming in, she is in.  The best time to breed is the thirteenth day, HOWEVER  it is an individual thing and she can get pregnant at anytime over a 3-4 week period.  Not likely, but possible.
Nancy
Separate her from any male for this period of time.