HI, and welcome
I would suggest seeing a Neuropsychologist for an evaluation. You are right, he should NOT be medicated without an evaluation. It could be one of the types of ADHD( there are several), or something else entirely. Medication is
A child may HAVE ADHD, but it is not what they ARE. Never tell a child they ARE ADHD.
NO testing? OMG...OK, yeah, before you medicate, do, please get a proper eval!
I'd also recommend reading a book or two about ADHD. The parenting suggestions are good for non-ADHDers too, so it's not like it'll hurt. Generically, ADHD kids don't respond as well to yelling/negative discipline, but more to positive stuff. Sticker/reward charts/jars, whatever you want, but basically a way of rewarding good behavior.
Also, repetitive stuff like that, I'm no expert, but I think that can be ticks (tourette's, etc.), not ADHD. Though if *none* of this is happening at school...suppose it could be just a kid holding it together at school & letting loose at home, but... Generally, the ADHD symptoms have to be present in more than one environment--both school and home, or home & activities, or whatever--to be "real" to the diagnosticians (yeah, there are exceptions). Have you come right out & asked his teachers if he can stay seated appropriately? Or has any attention issues? Because...well, some school districts, they're really wary about mentioning the "ADHD" word, and you really have to ask direct questions, not just rely on grades to tell you what's going on. Better to find it all out now, if he's got it, than hit middle school with undiagnosed ADHD!