Unaccompanied PCS

My husband is about to leave for a year in the spring and we started ttc last month before we knew he was going. I came off nexplanon in November and got my period in December and now I'm 10 days late. I took a test and got a negative on day 8. At what point do I take another? At what point do I call my gyno? I hate that I'm on a time crunch! It's turning me into a crazy person!!