First of all thanks dhlizard for your insightful help and effort you put on answering every question that MR forum members like my ask, you are a great resource for us jbrakers.
I promised I would report, so here it is. I tried your suggestion, but all I could find were guides on how to capture ibec and ibss files and none were on how to use said files.
So I left this morning for work desperate and hopeless. The iPhone was attached to the usb cable linked to my MacMini and before leaving I noticed that it had on the display the charging icon that appears when it's out of battery with the plug and bolt symbols. So I wall plugged it and left for work. When I came back a couple of minutes ago I went to pick it up and to my surprise the iPhone had revived and now works perfectly!
This is so weird. Now, I checked to see if I had saved the SHSH on cydia's servers and I found this on my cydia's home page: "This device has SHSH's on file for iPhone os: 3.1 3.1.2 3.1.3".
My questions now are: will I be able to restore in DFU mode in future, should this happen to me again? can I save the ecid on my computer too? if yes how?
Thanks a lot