I have 30+ payments waiting for confirmation for nearly 48 hours.

Fees have been 0.00020+ per transaction.

Today, I sent BTC from Bittrex exchange to BlockChain wallet.  Bittrex fee was 0.00020/BTC.

The Bittrex transaction was confirmed within an hour.

I do not understand how Bittrex transaction was confirmed in a short period of time and my other transactions with higher fees have not been confirmed.