To be honest I would say that 99% of competent people will agree to go to hospital if you tell it to them straight. I don't coerce or bully or force people to go to hospital, but I will tell them straight: You need to go to hospital if you have a frontal headache with visual disturbances because you could have pre-eclampsia which if left untreated can lead to the death of you and your baby. That is why I want you to go in; if it's nothing, it's ok, but if it's not nothing, it's proper serious. This goes for other 'do I have to?' complaints like bleeding in pregnancy, baby not moving for 24 hours, blah, blah... You were concerned enough to ring me, so take my advice when I talk to you!