Anki stats messed up

I was syncing Anki on my windows app and was doing Anki on my the AnkiWeb at the same time.
When the sync completed, all my stats changed, for e.g. I didn’t do Anki only for 3 days and now it’s showing I missed doing Anki for 7 days. Similarly, incorrect number of cards for every day are being shown for every day. Whilst I was syncing and simultaneously doing Anki on web, 60 extra revision cards showed up out of nowhere.

You appear to have done a one-way sync, overwriting your data. You may be able to recover from backup.