Heat cycle after having puppies

Question
Hello,
I have read that a dog will go into heat 4-6 months after having puppies. My Springer Spaniel had her first litter on January 14th this year. She doesn't have any signs of heat but our male dog has been mounting her a lot lately. It seems like it would be too early and, like I said, she doesn't have any signs but I am a little nervous. Do you think this is probably just a male dog being a male dog, or could there be more to it. Is there any way to tell without having to go to the vet.
I would really appreciate your opinion and advice.
Thanks,
Debbie

Answer
Hi Debbie, Unfortunately you have the start date wrong for counting when the heat cycle should be.  It would be 6 months after her last heat cycle (when she got pregnant), not after having puppies.  Counting on my fingers & toes, I believe she is getting close.  Hope this helps.

Dawn