Some will go away at the 2nd trimester. Some stays until the end of their pregnancy. Depends on individuals. Not all pregnancies are the same. Try to rub some axe oil on your temples and nose. Eat or drink something sour (this does not work for me, I nauseated more but you can try). I do bring along a small packet of dried sour cranberries with me just in case I need them. Alternatively you can buy the anti nausea band that you can get at Guardian which kind of help cos it presses on your hand temple or ask your gynae for some anti nausea pill