Help with E&M

Best answers
Hi, I signed up with Practicode and have gone through about 30 reports. I use the E&M calculator that is provided but it does not help. Every time I enter in all the details it gives me a code that is not matching the correct answer when graded. For example, one chart had a woman in her 40's go to the Emergency Department with a nose bleed. There were tests performed but no official diagnosis. She was discharged and told to take ibuprofen if in pain. The answer according to the Practicode was a 99285. My code according to the calculator wasn't as such as a high risk. I have searched every where for a step by step tutorial on the internet but its all concerning on how to pass the CPC so they give you the key components. Does anyone have any suggestions on how to figure this E&M codes out?