Yes, for being slow I'm pretty sure was the SD car as I removed it and it feels more smooth, do you know if there is a way to keep the SD in the phone?
First, try opening the SD card on your computer and searching for files of size "0 kb", (that's zero). If you see any media files that are zero kb, delete them. They are corrupted and are causing your phone's media indexing to get stuck in a loop. Symptoms of this issue are slow performance and the phone running hot from trying to process the file continuously. A battery-use examination or performance monitoring app will reveal "android media process" as the offender.
If this does not resolve the issue, you need to take more extensive action. First, copy everything on the SD card to your computer, then format the SD card using the phone, and then copy the data back to the freshly-formatted SD card. Then double-check it for files with a "0 kb" size.
If the problem persists, a last resort would be getting a new microSD card.