Hi Shazzaren
I would say this is a miscarriage, yes. I have suffered this sort of scenario twice and certainly all the health professionals I dealt with classed this scenario as a miscarriage.
Having said that (and I really don't want to sound harsh because I know exactly what it's like to go through), personally I don't see any benefit to dwelling on it and mentally building it up to be something bigger than it was IYSWIM. I think your idea of putting it behind you and planning for your next cycle is spot on, and that's exactly what I did with both of mine.
Even though it is technically a miscarriage, it can't really be compared to the emotional and physical suffering of a later miscarriage. I have also suffered a missed miscarriage at 10 weeks and there was a MASSIVE difference in the experience.
To be honest, I actually wonder to myself how many times I may possibly have gone through this chemical pregnancy scenario in the days before we were actively trying to conceive. I've never had cycles that were regular to the day, so back then I would never have noticed if my period was a few days or even a week late.
Having said all that, I really do not wish to belittle your experience at all and wish you all the best of luck with ttc. We've been trying for 4 years and have had 2 ectopics and 3 miscarriages (albeit 2 of them very early). I know only too well the pain of pregnancy loss and that's why I chose not to dwell too much on the very early miscarriages.
One other thing - with regards to tests and investigations, I would certainly include this as a miscarriage. I was immediately referred for tests after 3 miscarriages despite the fact that 2 of them were so early and no doctor has ever questioned me on it.