yes, you are not alone. It is very very common for kids with Aspergers, especially those with lighter symptoms (in a way) to look ADHD, Anxious and ODD. Really it is about how hey are perceiving the world. Things dont feel right, they dont interpret social situations (including school rules, subtle non written codes, how to maintain friendships and to be understanding of others etc.). Many have issues with transitions (changing classes, switching routines, going from place to place, waking in the morning and getting ready for school, etc.) Sensory issues are also common. motor challenges, especially fine motor problems can happen. Also there are processing issues like auditory and language processing problems. These things can all appear to be the child not being able to attend like ADHD. You will need help figuring out if he has one, the other, or both (or many, smile).
There are lots of stories here, and many will post them for you. Your son is at an age where it is often finally figured out because there are more demands on kids socially and kids are expected to handle things with less support in class. The pont is, yes, he certainly can have both and it also can just be Aspergers that has not been appropriately accomodated for. It is wise to do as you are doing, have an evaluation. Many of us here use neuropsychological evaluations which look at most areas of development and connect the results with how the brain works. It helps to differentiate between the different diagnosis. It is a process.
Let us know how things move. there will be many questions coming your way here....people have great experience and most of us have been thru it big time! dont be afraid to ask anything! Welcome!