No need to panic, it will be confirmed, but next time try to send the transaction with more fees than before. I had a transaction which was unconfirmed from 11 hours so I used a website and accelarated my transaction and it got confirmed very soon when viaBTC found a block and the best thing is its free there is no fees to use it. But I will advise you to send bitcoins with more fees.
https://www.viabtc.com/tools/txaccelerator/My transaction first found in viaBTC block they helped me really much.
If your BTC transactions are "important", then I would do both of the above suggested by
lolxxxx. All of my transactions are "important", I do not like waiting around for hours or days for confirmation.
Pay more so your trx gets through! For simple transactions of size (over $100 worth of BTC say), I just pay around $1.00 or so (more if there are LOTS of unconfirmeds). For larger amounts, I pay even more. If your trx is complex (many small inputs), then pay even more... The most I ever paid was about $3.00 when I had a large trx that I wanted confirmed quickly.
$3.00? Confirmed in the very next block, so I was perfectly happy.
Also, the ViaBTC service works pretty well IF you get in just after the top of the hour (say withing 3 minutes, I have never failed to get my trx accelerated by acting fast after the new hour begins). ViaBTC's service sometimes works very fast (next block sometimes, even if it is not won by them), but has never taken more than two - three hours for me. Make sure that you pay over
BTC0.0001, but I would pay MORE to make it attractive for them to confirm. IMHO.
If your transactions are very small, I cannot offer any other advice.