I couldn't find my ledger nano until about 20 min ago and 90% of my holdings were in altcoins... Is there anything I can do?
I assume not, but figured if I was going to ask, I'd ask here
The coins you had on your ledger will be on the BCC chain, so you have these coins. You will have every BTC you have in the BCC chain assuming you control the private keys.
Obviously the altcoins have nothing to do with any of this. Also why are you keeping 90% on alts? that is insane unless you don't have that much money and you are taking big risks.
OP does not store BTC in the previous wallet. So, OP will not accept BCC although him keeps the private key.