Yeah, that might be what's happening. In Mutiny, if you select the pending transaction, it'll show you a pop-up with all the transaction's information. Click on the link at the bottom next to "TXID", and it'll take you to where you can see your transaction in the mempool (be sure to scroll down and click on "see more details"). That way, you can verify where it is, and get a good idea how much longer it'll be until it's confirmed.