Could be a relaps of your Lyme/co-infection symptoms, or could be something else. Low blood sugar can do this, as can fluctuations in blood pressure. Also, orthostatic hypotension can do this if you get these episodes after a change in position or staying in one position for too long (esp. standing or lying down). Best thing to do is talk to your doctor about this since it is a new symptom for you.
Chronic Lyme Disease, Gluten & Sulfite Sensitivity, Many Food/Inhalant/Medication/Chemical Allergies & Intolerances, Asthma, Gut issues (dysmotility, non-specific inflammation), UCTD ("Secondary Lupus-Like Syndrome"), Osteoporosis, Pancytopenia, chronic malabsorption/malnutrition, etc.; G-Tube; Currently TPN-dependent.
Meds: Zofran, Pulmicort, Heparin (to flush PICC line), Claritin, Colloidal Silver (used topically), IV Milk Thistle, probiotics.