I'm glad you brought this topic back up. "Sipping through a straw" has to be the worst possible advice for a new pipe smoker, and over the last week or so I've entertained the idea that the advisor was either joking, hated the OP, or a troll.
Yes, you have packed too tight if you have not getting anything, or the bottom dottle has swamped with moisture. Imaging drawing that hard, most likely increasing the blood supply to your mouth, and exposing more tissue to the alkaline smoke and steam from the hot bowl.
Try this: Drop the first tobacco into the bowl by gravity. Wad the next pinch a bit and place it on top with a gently push. This is relatively loose but your bowl should not be full while you are learning. Wet your mouth - something slightly acidic like tea or coffee is good but until you are comfortable with the process avoid alcohol, and a light film of saliva is helpful too. Now, light and enjoy creating a dense plume of smoke during the char with gentle draws. Some tamp a little, and do it again. After this, your draws should be done only by opening your palate (expanding your mouth cavity) through partially open lips so you'll get fresh air at the same time. Never "suck."
As you begin to find flavor without pain you will get a little more aggressive. Just avoid "sucking through a staw" and any sense you are getting steam, and more of your smokes will be flavorful.
Good luck!