I'd encourage an HPT with first morning urine. If the outcome is a BFN, then given the timing of your cycle, I suspect you're symptoms are associated with the change of hormones between your estrogen phase and the progesterone (luteal) phase. The shift from one to the other can bring on headaches, migraines, dizziness and/or nausea. Make sure you're taking a multi-vitamin with iron and b vitamins to counteract the symptoms.
i would do a test itl tell u either way by now gud luck !