16 DPO positive test, digital test negative

I’m so confused! I’m 40 years old, I’ve had two successful pregnancies, and am not TTC our third but not preventing either. So I haven’t really been tracking my cycle, but if I had to guess I’d say I’m about 16 DPO.

3 days ago I realized my period was late (I’m NEVER late), took a Wondfo test and got a faint line. I realized the tests expired several months ago, but from what I’ve read this would just mean I’d get an even darker line on one that isn’t expired. I took several more tests from the same box over the next two days and continued getting the faint line.

Today I picked up a Clearblue digital test and it read “Not Pregnant”. But I still haven’t gotten my period and have other weird symptoms I don’t normally get before my period, like constipation and extreme bloating.

Is it possible that it’s still too early for a positive digital result? Perhaps I didn’t ovulate when I thought I did? I also have an ovarian cyst which the doctor told me is harmless, but is it possible that it could have caused a false positive?