If I consumed an altnoid that was legal when consumed but is now banned and there is record of me buying that product, will I get in trouble with the law?

Apologies if this sounds too paranoid but I want to make sure. I'm a complete newbie with this please forgive me.

When I was living in Japan 2 years ago, I bought a pack of altnoid gummies online (don't remember the exact strain name but I know it's banned now) and had no issues or anything, I consumed it privately and discarded everything privately. 

maybe a couple of months or so after I left, I heard news that that exact strain I consumed was officially banned. I ordered it online so I assume there is some kind of record of a purchase of it from me. I used an app where you order it online but pay via cash at a conbini, so I'm not sure if that's different somehow. 

I no longer live in Japan but would like to visit again, and was worried if there is any possibility at all that consumers who have consumed a now banned altnoid can possibly get in trouble with the law, especially when entering the country through things like immigration. Even if it was something consumed from years ago, that the police could track it down to me and that I'd get in trouble for it somehow.

I want to make sure what the updated laws are and be sure it's not something that I am only "getting away with" because I'm not in the country right now, and that it would catch up to me if I ever went back. I have this probably irrational fear of them arresting me as soon as I land (it's silly I know, but I just don't know how strict they are). My assumption is no but I don't want any anxieties during any future trips, so I just want to make sure with someone whos much more knowledgeable about this and quell those anxieties if possible.