Something's wrong with my Minecraft login?

I've got a quite major and annoying problem with my Minecraft login.

So, later some days ago, I brought Minecraft. I played it just fine but my stupid cousins who play the cracked one got really jealous (they're both kids!) and said that they'll hack my Minecraft. They pretty much built a team of people (maybe it's a fake). I was playing my Minecraft normally until I ran into this weird problem.

Now each time I try logging in to Minecraft with my correct password and email, it says that my login was not correct. I have to click "Forgot my password" and reset my password to my normal Minecraft password over and over. Today it's a different problem, slightly, which didn't happen before. Now when I try logging in it gives the same error even though both of my inputs are completely correct except that now Forgot my Password doesn't work either.

Can anyone tell me some instructions to fix both of these? My password is strong; a LONG secret word which I made up and only I know of. I know it's kinda weird I built a word for a password but meh. Just, how do I fix this problem with my Minecraft.

Do you share a computer with your cousins? Also you should be just logged into your minecraft account whenever you start your minecraft launcher. Also i don't think kids would be able to hack your account because well… They're kids lol. You should just set to where you're automatically logged into your account and ready to play minecraft whenever you start your minecraft launcher. If you suspect it's your cousins which i highly doubt because they're "kids" then just talk to your mom/aunt/dad/uncle and i'm sure they'll fix the problem.