I have low blood pressure and I get nosebleeds pretty much every time I sneeze or blowy nose. It's because the blood vessels in your nose are swollen during pregnancy. How much water do you drink? I drink a little more than two litres a day (I think that's about half a gallon in american measurements). If I don't get enough water, I get dizzy and have a headache, so that could be part of it for you. The nausea could be a reaction to the headache, or any kind of smell...I don't get morning sickness and my early pregnancy nausea is gone now, but I occasionally get nauseous when I'm just around stuff that doesn't agree with me. You could check with your doctor if you're worried, but all of those symptoms you described are normal pregnancy symptoms, so it could just be a bad couple days.
My blood pressure is usually lower than normal . I'm not sure how it is right now.
How's your blood pressure? I know high blood pressure can make your nose bleed and have headaches.