If it went in and didn't give you any kind of error message, it worked. Inserting a SD card doesn't increase your "Internal" phone memory, it just gives you "External" memory.
"Internal" memory is needed for apps and the phones OS. "External" memory can be used for photos, music, videos, contacts, etc.
If you are trying to add more "Internal" memory so you can run more apps, well an SD card may or may not help you there. For that to work you need 2 things. 1. Your phone has to be running, or upgradable to, Android "Marshmallow" and 2. The manufacturer has to have not restricted that ability on the device. Which does happen. If you are running, or can upgrade to, "Marshmallow", then try the following.
How to turn external SD card...