Relax and don't stress yourself. It's most important for you and the baby. A headache with bright spots may occasionally be migraine ( which again is just a type of headache which is curable)... But before jumping to conclusion it is always better to see a physician and your gynaecologist to finally arrive at a diagnosis and then prescribing the necessary medicines, if seene necessary. Donot stress out on medical terms from the net searches, Better ask your doctor, and rest assured you will be just fine.