I wear and smile and some blush slapped across my face But underneath there's a monster that can't be tamed I'm 'bout to lose it, I feel it moving You try to test me for weakness then go too far Instead I'm caving I'm eager to make my mark You'll never forget just who you've messed with Don't underestimate me I've got a fire burning inside And if you try to break me I can't promise you I'll be kind I'll show you what I'm made of Just when you thought I'd given up Don't underestimate me I've got a fire burning inside I know the drill you'll come back with a story to tell And it'll be that story that I know so well You didn't mean it You're heart is bleeding And I'd like to think it's true But I know you better than you do I tell you Don't underestimate me I've got a fire burning inside And if you try to break me I can't promise I'll be kind I'll show you what I'm made of Just when you thought I'd given up Don't underestimate me There's a fire burning inside It's not healthy what you're playing It's not healthy what you do And you'll deem yourself as crazy If you think I'm scared of you And you might want to be careful Where you look and where you step You wouldn't want to wake up With a demon in your bed Don't underestimate me I've got a fire burning inside And if you try to break me I can't promise I'll be kind I'll show you what I'm made of Just when you thought Id given up Don't underestimate me I've got a fire burning inside