one week late

Kyrstiana • Married to the love of my life for one year. 22 years old. Currently TTC!
Please help a girl out. I had my iud taken out three weeks ago and we have been doing the BD like crazy since. I'm officially one week late on my period, but I keep getting negative tests! Am I testing too soon? Could my iud making me be so late? I'm super frustrated because I feel like I'm at a dead end until my period comes.