This may be a stupid question

But me and my husband are naturally family planning cause my body rejects any type of bc possible and I have a horrible reaction

3 days ago I took a ovulation test and it was negative like so negative the line was barley there , and we did the dance ( he pulled out of course) but now 3 days later I have a BLAZING positive… is there a chance with the precum??

We’re not actively trying right now but I didn’t think it would be positive since I just got off my period not to long ago