Hi Joan.
This is a nice relaxing holiday you have picked. There is a small shopping centre just across from the hotel, but I was there right at the end of September 2013, and not much was open. I believe that there is also a small supermarket and a Chinese store (that reputedly sells everything), just down from the hotel (turn right). The beauty of the all inclusive is that you don't need to be buying a lot. There will be a bottle of water in the fridge in your room when you arrive, and water (and of course all drinks), are available all day. Punta Umbria is about a 15 minute walk away, and there is a trip to Huelva during the week for shopping mainly. The trip to Tavira is also very useful for shopping. It was cheaper than Spanish prices as well when I went. :)
There is a small shop in the hotel. I think they stock basic stuff, like sun cream etc.
To be honest I just enjoyed the all inclusive experience when I was there (the food was consistently good, best buffet I have had anywhere), but the problem for me was the humidity. Also, make sure you take loads of mosquito repellent!