Toddler meltdowns/tantrums

My son was the happiest baby and never gave me any trouble and then I believe it was around 18 months when he had his first tantrum or meltdown and now he's getting closer to 2 he seems to be having them more often he will be 2 in March and most of the time his Tantrums occur either when he's being told no or he has these meltdowns when he's woken up while he's sleeping at night or during naps and he just screams and cries and is inconsolable for up to 10 minutes or more and I just don't know what to do. I am upset i can't get him to calm down and my mom keeps freaking out saying that this isn't normal and she's never seen a kid do this before. I've heard of the terrible twos, I'm not sure if that's what this is or if there's something I should be concerned about is anybody else having these problems? How do you get them calm down? He either tires himself out or i can get him to calm down by distracting him with his favorite show or toy. Is there a better way to deal with this behavior?