I was mining on test-net miner and was trying to send ether to coinbase for the first time just to test a transaction but the transaction never sent and is still showing pending transaction. After restarting ethereum mint all the ethers are gone, all of this happened while the nodes were not fully synced it was syncing for a couple of days and still not done yet. Are my ethers really gone, can I still retrieve them? if I check my balance on etherscan.io it says balance 0.. I am not sure if my address has changed or not I did not keep track.
Ether from Test-Nets cannot be sent to accounts on the main net, where the coinbase accounts are running on. Successfully mining a block means having it confirmed by the network, and this is unlikey to happen if you mined it while not fully synced yet. So keep in mind: Sync first, then mine, and do not mix up test-nets with the main net.