what shall I do now?
My transaction also got stuck unconfirmed since 12/31/2917 because of CEX.IO paid too small fee. There's chance you may have been on the same tx as mine. What's your tx ID ? Here's my:
https://blockchain.info/tx/e7651c62ed1b693a561b36f319de0184ee6ea408654994d1282279a2eace985c
If neither of these have still confirmed, you can look on the services section as there's a few free TX accelerators that might help you with getting your transaction confirmed. Viabtc/antpool accelerators are slow for the free ones or expensive although the transactions are very large. And also contact cex.io's support as I'm not sure if cex still mine or not and they can add it to their miners' priority list.