I created the account in 2017, but did 0 lessons and 0 reviews. I started this week for the first time – is this going to affect my levelling up speed?
Obviously if I check my average levelling up speed, it is abismal 'cause I’ve been technically stuck at the same level for months.
Considering you didn’t do any lessons or reviews prior, no it won’t hinder or affect you at all ^^
And as far as checking your average leveling speed, if you check your stats at https://www.wkstats.com/ and look at your level duration graph, you can click on a level to exclude it from your stats in order to get a more accurate average time/level for future reference
Here’s a list you may want to go through since you signed up quite a while ago.
The WaniKani FAQ which gives you the 101 on
a) Before You Join
b) Common First-Level Problems
c) The Basics
d) Learning Method
e) Account
f) Sect Names Other
The WaniKani Guide (…also known as “how I learned to learn ~2,000 kanji.”)
The Ultimate Additional Japanese Resources List! which is a long and thorough list of Japanese resources that the community has worked hard to gather together and is consistently being updated.