No, in case you transaction was not mined, you didn't loose any funds. Neither sent by this nor by subsequent transactions. The reason why subsequent transactions are not mined, is because they use nonces higher than the nonce of the problematic transactions, but transactions has to have no gaps in nonces in order to be mined. So, if you've sent three transactions from the same address with nonces
2, and transaction with nonce
1 wasn't mined for some reason, then transaction with nonce
2 will not be mined as well. In order to resolve such situation, you will need to publish another transaction with nonce
1 from the same address, and once it will be mined, subsequent transaction will be unblocked.