Hi,
Yes it is completely normal for your pup to be losing teeth at this age. Normally your pup will go through this without you ever knowing as they generally swallow the teeth as they come out. I am sending you a link that explains the cycle of your dogs teeth more thoroughly along with information on keeping the teeth healthy.
http://dogs.about.com/cs/disableddogs/a/basic_dental.htm
I hope this helps. Please let me know if you need additional information.
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