Hi Sue Ellen! I'm on Weight Watchers too, and noticed quite quickly that I had to adjust my basal insulin as well as my I:C ratios. (I'm on a pump by the way.)
I'll let you know one nice thing, as POINTS in WW are very precious! Don't use food to correct your lows. Run out now and get some Glucose Tablets. I get mine at Wal-Mart (their brand) and they are 1 POINT per FOUR tablets.

4 tablets is 16 gms. of carb, and they work quickly. After you've had the tablets, grab a banana or even better, slather a Tbsp. of low fat peanut butter on a 45 calorie slice of Sara Lee bread.

That's 2 POINTS... I usually don't need the bread and peanut butter, because I usually go low around a meal time, so I just eat my normal meal.
Good luck!