70 is normal for you since you don't have PKU. The units are Micro Moles per Liter in your blood. I had a level of about 1800 micro moles per liter and my short term memory wasn't working well. I'd stumbe in the morning. I had headaches a lot and felt dizzy, but not like the room was spinning so it is best to describe it as disoriented. Some PKUers call it feeling cloudy. I don't understand that myself. It's as if you had 3 or 4 beers minus the happy,euphoric feeling you get with beer.
I have a group on facebook called PKU Tools. I am a software engineer and since I need something to help me track my diet and calculate my PHE and protein and excanges I decided to write a program for us PKUers and the families. This app is $100. NOT! its free. I will post on PKU.com once it is done or you can join the facebook group to see the progress and capabilities as they are currently.