After a little time has passed, a tombstone will appear where you killed Cale. If you interact with the tombstone, you can pay souls to speak with Cale's spirit, which will allow you to obtain the key.
This same technique works for all (or almost all?) NPCs in the game. If the NPC in question had items for sale, you're also able to browse their wares this way.
With all the different versions out there, the publisher made this quite confusing. If you have the DX9 version of the original game with the Season Pass, you can upgrade for 20$, without the Season Pass for 30$.
Scholar of the First Sin (SotFS) is basically a "complete edition" of the game. It includes the base game and all DLC. In addition to that, there will be a patch that adds things like new NPCs and re-balancing that is already included in the SotFS edition, but will be available as a patch for the original game as well.
The benefit of upgrading your DX9 to the DX11 version are improved graphics (obviously), and gameplay changes that are exclusive to the DX11, Xbox One and PS4 version. These include new placement of the enemies (e.g. Heide Knights actually being in Heide's Tower) and more online players in a single session. These changes will not exist in the DX9, Xbox 360 and PS3 versions.
The SotFS edition for DX9, Xbox 360 and PS3 is just the patched original game plus DLC, nothing more. Players of both versions will be playing on the same servers. Players of the DX11, PS4 and One versions will play on different servers, which means you can no longer play with people who have the DX9 version on PC with the new version. You will still keep the original version though.
Here is a table that details the different versions (found on videogamer.com):
Best Answer
There is a merchant near a bonfire in the Forest of Giants who will sell lifegems in limited supply. After talking to her a few times, and defeating the boss of the forest, she'll move to Majula, at which point her supply of lifegems will become infinite. You'll know you've talked to her enough because she'll talk about it being time for her to move on.
However, it seems your real problem is that you need more Estus Flasks. You're able to get more by finding Estus Flask Shards and giving them to the Emerald Herald in Majula. There are three Estus Shards you can find fairly early on.
The first can be found inside the well by the mansion in Majula. Just knock over the rock down the well and an Estus Flask Shard will appear.
A second one can be find in a room above the second bonfire in the Forest of Fallen Giants. The door will say it's locked, but you can actually break it open if you just attack it.
Finally, you can find another Estus Flask Shard inside the mansion. You'll get the key from Cale the Cartographer inside the Forest of Fallen Giants. You'll find him shortly after the second bonfire inside the Forest of Fallen Giants. Just go down the ladder next to the bonfire, and when you get to the area with the large tree drop down to the area below. You'll then find him inside of a cave on the side opposite where you came in. Just keep talking to him and he'll eventually give you the key to his mansion.