Aw mama, I totally get the worry, one of my mum friends went through something similar last year and the stress alone made her cycle even more delayed, it's such a vicious cycle talaga! The good news is your PT is negative so at least you can rule that out, but honestly 43 days with a normally regular cycle does need a doctor's eyes on it kaya good call scheduling with your OB, there could be so many reasons from stress to hormonal shifts to thyroid stuff that only proper tests can tell. In the meantime try not to stress yourself too much (easier said than done, I know!) because sometimes our bodies just go haywire from life changes or even just our nervous system being in overdrive, pero the doc will sort you out soon. Hugs, and let us know how your appointment goes!