If there is no double spend, most likely a transaction will get included in both competing blocks so when one block is orphaned then another block would still have your confirmation.
That's quite possible, yes. If both mempools had a record of that transaction, both could have included them in their own blocks. It would really be interesting to see some statistics on stale blocks regarding how many of the same transactions get included in competing blocks and remain valid and confirmed once one block gets orphaned and how many become unconfirmed and return to the mempool. I am not sure if that is possible though. I am not talking about the overall count of orphaned blocks but the status of their transactions compared to those that got mined in a competing block.