When should I take another test?

I ovulated cd9 based on temps, and symptoms. I took a test today and I thought I saw a very faint line and someone else they could see it I'm on cd 16 in 30 min. I have another test same brand the 88cent ones from Walmart. And I was wondering when I should take another one. I've been having some different discharge, I'm having lots of cramps, I'm nauseous, and I'm also having leg cramps I've been pregnant before but from the beginning had no symptoms so this is kinda new. I'm 10 days away from my period