It seems that your are a U.S. citizen. Since U.S. citizens are visa-exempt, I'm assuming that you have a "Visitor Record" rather than a "visa." My common-law partner also has a VR and we have travelled to the U.S. 9 times since he has been in Canada with a VR. One all of those 9 trips, the only questions were routine things like how long was the trip, purpose of your trip, where do you live (we gave the city in Canada), do you have anything to declare, any alcohol or tobacco. We did get warned a couple of times that the VR was expiring soon and that we'd better get the PR application in and another time that we'd better get the VR extension application in, but there was never a hassle at all.
Before he got a VR, my partner was pulled aside for secondary inspection 3 times. After the VR, it's always been very fast and no secondary inspection. Of course, they can always deny you entry if they have some reason to do that, but you won't have a problem.