Tick head stuck in dog

I know this has nothing to do with pregnancy or anything womanly or human but I need some advice/help.
My dog had a tick, an orange one, and my sister (who is impatient and arrogant) improperly removed it. The head is still stuck in my dog though. The site is red and puffed up and is the size of my pinky fingerprint. The site kind of looks like the top of a baby's head with a soft spot, so it's round but slightly lowered in the middle, assumingly where the tick head is.
I love my dog to death and I'm very attached to her, she is one of my great emotional comforts and we saved her from dying when she was a puppy. So please I really don't need mean comments I would really like some help on how to treat her.