Whenever i play dota 2 my macbook pro gets really hot. is this ok?

I just recently got my macbook pro 13 inch with normal factory specs. i downloaded steam and got dota 2 which is btw a really fun game. but whenever i play it, about 10 minutes in my computer starts to get really hot on the bottom. it gets hot to the point where if i put my hand there to see how hot it is, it starts to burn and actually hurt my hand and it doesnt feel good to keep it there long lol. but im wondering if this is normal and if its ok to keep playing? When it gets that hot it makes me want to stop playing because i dont want to progressively fry the components overtime as i need to keep this computer for a long time. i almost forgot to mention that im playing on pretty settings as far as graphics. i have alot of things turned off including shadows and antialiasing and other stuff that i really dont care about and the game still looks great but the computer still gets really hot. any help would be appreciated and thank you!