I'm really worried as I have had awful period pains for the last week (which is quite normal for me as I have endometriosis). I finally gave into the pain yesterday as it was even worse and I was in meetings all day and took 2 feminax ultra tablets. Me and DH are trying for a baby but I assumed with the pain worsening and a -ve PG test that it hadn't worked for us this month. Now I have no sign of period and am worried in case I'm PG as your not supposed to take Naproxen. Anyone know the effects? I'm scaring myself reading on the internet about it....