Am I out?

So on one app it says I ovulated on the 17th of Dec and the <a href="">Glow app</a> says the 19th. I'm either 5-7dpo now and my breasts are already sore . Does that mean my period is coming and I'm out? I'm also having bad cramping pain and lower back pain which could also mean period. Supposed to get my period on the 3rd of January . Help please ladies!