If not, you would have a blown laptop.
As to the guy, not bad advice. There are tomes of battery lore on the web so anything I write could be countered with something on the web.
Let's go with "All good. Carry on."
So I just changed the battery of an Acer aspire E-14 (AS16A5K battery) I have two questions I disconnected two thin black and white cables, I connected them again but not sure if it was the right order and if they were important because my laptop seems to be working just fine.
Second question, do I have to charge the new battery before? The guy that sold me the battery just told me to charge it 5-4 hours.

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