http://www.breastfeeding.asn.au/bfinfo/excercise.html

As for let down (no such thing as a silly uestion btw):
Yes that tingling feeling is let down

This comes from the ABA booklet "An introduction to Breastfeeding":

The let down reflex makes most of the milk in your breasts available to your baby. There are cells around the alveoli that can contract and squeeze out the milk, pushing it down the ducts towards the nipple...The letdown reflex is a response to your baby's suckling. It may happen if you see or hear your baby or even just think about him. It can also be triggered by feeling your breast and nipple area with your fingers or by using a breast pump...Let downs usually occur more than once during a feed; however most mothers will only notice the first. These other let downs occur in response to changes in a baby's suckling. Some mothers feel the let down in early days or weeks, but later find that the feeling goes away.