i didn't saw that i paid a to low fee on tx1. so the only thing i can do is wait?
Depends, which wallet do you use?
Nope If a transaction goes unconfirmed for too long, it will eventually disappear from the network and I think the The wallet that he sent it to cannot spend it because it's not confirmed. So you have to wait until it disappears from the network and send an entirely new transaction.
That is incorrect. The transaction only disappears if it is no longer rebroadcasted. Some wallets will continue to rebroadcast the transaction so that it stays on the network, others don't.
Technically the receiver can spend the bitcoin from that transaction, just that if that transaction remains unconfirmed then any subsequent transactions will be unconfirmed as well and would also disappear if this first one disappears as well.