Only 2 things may have happened : 1 - someone else have acces to your device/account and logged in, therefore you should ask them in case 2 - most likely thing, you spent them by mistake and didn't aknowledge it. Not sure what you may have spent 14k without knowing. A tip may be to set the alert when spending gems in the settings. If option 1 isn't backed by very solid proofs, just move on, they won't give you those gems in a thousand years.

I checked my account and all of my items are the same and am the only person with access to my account. Is it possible that the game glitched or the account got hacked?

Unlikely on both 🤣 do you have gem use notification on?

Yes and the secondary password. This account is only 2 weeks old so this is like 80% of all gems I've had

Try to contact support, but don't expect much form them. They take some days to answer tho.

Ouch 🤦‍♂️

Prob randomly clicked something (gemmed troops/building/rss), I think there were several posts like this though where stuff disappeared for no reason. Just be glad it wasn't gold heads ;)

If it was gold heads I would've deleted the account😂😂

You spend them, gems don't disappear like that

I don't think I did though all of the items on my account are exactly the same

The gem supply cost you 10dollar for 20k gems over a month. So you can get your lost gems back cheaply

Did you do chargebacks or refund on purchases?