The Waiting Game

So I'm about 6 DPO and for the last 3-4 days my stomach has been crazy upset. I've had lower cramping and feel like I'm going to start tomorrow. Usually, though, cramping and all doesn't start until next week for me when it's AF related. Also (TMI coming), CM is like egg white-yellow.. Am I paranoid or could this be it? I'm telling myself it's most likely AF bothering me sooner than normal.