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If your dog is between 5months to 9 months of age ( some as young as 4 months and as late as 12 months can also experience their first heat) then she is most likely experiencing her first heat and these symptoms are very normal. Other changes you may notice are increased frequency to urinate, attitude change (temporary), and mammary development. Be sure to keep her separated from intact males and watch that she doesn't try to escape as some females do.
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