7 days late, no period, negative tests

I’m still trying to figure everything out. A little background. Husband and I are both active military, he’s currently stationed in South Korea and I’m in Hawaii. So baby making time is currently hard to come by. We’re currently spending a long vacation together in Japan (21 days) in order to sightsee and of course try and have our first (we couldn’t try before the military separated us earlier this year).

According to my charting, I should have ovulated around the 19tj or 20th. My period was originally supposed to start on July 31st (Hawaii time). I took a pregnancy test today and it came up negative. I would say since about 26-28 July I was getting symptoms that I thought would signify that my period would start soon (really hungry, back pain, kinda grouchy and really tired), but it’s now the 5th Hawaii time and the 6th Japan time and no period, and all negative tests. I’ve never been this late before.

Any advice?