No, it was 10 days to a few days more depending on when a country switched to the Gregorian calendar.

The central problem here is that the "year" (specifically in regard to the seasons) is not an integral multiple of days, it's actually about 365.2422 days. This means a 365 day year will have the dates of the seasons drift by nearly a quarter of a day every year.

The way calendars have fixed this is with leap days. A leap day every four years makes the average calendar year 365.25 days long, a lot closer to the actual year length. This is the Julian Calendar adopted early in the first millennium ce. The problem is that pretty close is still a little off, enough for the seasons to drift dates by many days by the middle ages.

The Georgian Calendar adds two extra leap day rules. On years divisible by 100, the leap day is skipped. This drops one day per century or 1/100th of a day from the average year length, hitting 365.24, closer. Then it adds back the leap day on years divisible by 400, adding 1/400th of a day to the average year length, bringing it finally to 365.2425.

Still not exact, but only causing a drift off the seasons by one day every 3000+ years.

I should note that the days weren't lost or anything, it's simply a matter of switching how they are designated. If you wanted to you could retroactively relabel all old Julian Calendar dates with their Gregorian Calendar equivalents, and then you'd never have a sharp change in dates from one day to the next. But it's easier to just add a note of which calendar system is being used to refer to a date and take that into account accordingly.