Early testing / when is the best time to test?

I’m preparing my body to TTC and have been spending time learning more about my cycle, ovulation, and timing. Some of this is still new to me, so I hope this isn’t a silly question!

My partner and I aren’t actively trying yet but aren’t using any form of contraception either. I’m currently 8 DPO and have been experiencing sore breasts since 3 DPO. I was especially sore when rolling over in my sleep last night which is unusual and new for me. This led me to take a test this morning, but it came back negative.

I’m wondering—should I test again tomorrow, or is it still too early to get an accurate result? I’d love to hear your thoughts or advice!

Thank you!