Hi Priscilla!
Just like other countries, there are so many options for online shopping in Pakistan. Being a girl, I often shop online at the official store of one of the best women designers in Pakistan -
The prices vary from product to product. Some products are cheaper online while some are cheaper at stores and not online.
Delivery is often fast. You'll get the item within 2-3 days if it's a local order and it will take around two weeks if the item has to be dispatched internationally. Further, there are some online stores that charge you for delivery (approx 200-300 PKR) while the delivery on some online stores is free.
Let me know if you've any other question. I'll be happy to answer that 
Best,
Urooj K.