Advice please x

Can someone give me some advice please, so I have been having sex since the 8 March.. the 13th was my fertile window and ovulation is today (still having sex) past two days feeling pretty nauseous.. (I’m sometimes like that anyway usually don’t feel sick all day like I have been ) I done a test yday came back negative.. I’m presuming it’s too early when will be the best time to test I’m so nervous yet excited🙈