File Share Encryption

I saved my personal private PGP key on an external encrypted drive and also a USB flash drive. Question is, since I have used the flash drive on secured university machines for lectures, should I assume it's been compromised? Or is there no risk?

There is no way to know if this risky behavior actually resulted in someone capturing your private key.  Hopefully you at least have a secure passphrase to protect it.  The passphrase is hashed to produce a symmetric key for its encryption.  When you enter your passphrase, your private key is decrypted for use.  So even if someone has captured your private key, which you certainly don't want, a secure passphrase helps mitigate this risk.

thanks Tom, the only anyone could have taken the file is for univerity IT to fecth in from a pc when i was connected to copy files -- doubt it.