It should not bowl you over like that.  What are you using in your tank? I used to use the drop ins and had bad odors.  I switched to the 
Geo method and haven't had any issues since.  Make sure there are no drop ins in your tank before switching (don't ask me how I learned the importance of that one:S).  Always add a few gallons of water to your black tank after dumping, you don't want it to dry out and form the dreaded stone mountain.  We have left stuff in our tank for almost a month in NC summer heat without any issues.