[SOLVED]Mod not loading like it wasn't existent

[Cosmos]

My account in this forum is really new, but I already play Minetest for a long time.
So basically, the mod I created (not published yet) was working as usual while I was testing it yesterday, it worked perfectly.
But today.. I've decided to add some new features in the mod and when I tried to test it, the mod wasn't there. I've searched in inventory and the nodes and items that I added weren't there, (if you're wondering, yes registered the nodes and items).
I tried to use the /give command, but it said "Can't give an unknown item". After that I discovered something: another mod, (which wasn't made by me), wasn't there too.

I use Minetest v0.4.13

NOTE: The mod suddenly is working again, but feel free to reply if you know why.

[deezl]

Always good to look in the debug.txt to see if there were errors that posted during the startup. Also a good idea to go ahead and update your game. Minetest is on 5.0.1 now.