It is normal to worry, especially when you read about how many times you baby "should" be moving about on average... i started to worry after not feeling my baby for 5 hours after one huge ...HUGE movement. (looked like a big wave was crashing in my belly) and after i tried all the things mentioned above (cold drink, even hearing bubs heart beat on my doppler wasnt enough as i thought it was mine!!) i called the hospital and went in for monitoring.. they were really good about it, so dont worry that you are worrying to much and go with ur instinct as it is usually right.