Trying to get my kindergartener to like and do homework.

Hi everyone. My oldest daughter is 5 years old and has just started kindergarten a few weeks ago. I have been going through the toughest time trying to get her to stay focused or even interested in doing homework. Although to me it seems so simple just to draw a few shapes and write her name or count the birds, she just does not want to do it. I've noticed that she's starting to write the letters in her name backwards when before she'd  write it perfectly. Her attention span is extremely short. She rather go see what her 3 year old sister is doing or go watch tv. Is it too early to suspect she might have ADD or something? I'm trying to tell myself that I should give her more time to get in the habit of doing homework but I'm starting to worry. Is anyone else having or had this issue? Does anyone have any advice?