Day 48 ... when should I test again?

Should I test again? (and when?)

So my husband and I have been "trying" for 6 months now. We are young and healthy and not in a huge rush, so we haven't "done" anything besides not use protection.

We decided to start "really" trying next month ... charts, no more caffeine for me, etc. which is why I joined Glow & got the app (I was previously using Clue for my cycle). My period won't come, though. My current cycle started 48 days ago. I took pregnancy tests on day 29, 36, and 40. They were all BFN. Super super negative. And they were 10mlu tests. So I'm pretty sure I'm not pregnant.

Does anyone have any ideas when I should test again, if I should schedule a gyno appt.? When I should expect AF? I'm trying not to stress too much because I know that can have an effect, but I also want to move on from this cycle!