Im pretty sure the E is just telling you that it is running on the
Edge network. The same network that the iPhone runs on. It isnt nearly as fast as
3G. But as far as your reception problem goes, I have found that there was a recall of sorts on phones made during a certain time frame that were not equipped with adequate antenna's. Mine was in this category and AT&T sent me a new phone. So as long as your phone meets the date requirements and hasnt ben broken, soaked or have a lot of significant damage they will replace it. Just read the info on this forum and call the number.
http

slash slash)gizmodo.com/gadgets/cellphones/samsung-official-response-on-blackjack-issues-326675.php
I had to botch the link up because I dont have enough posts to post straight links. But just the // is messed up.