Test result issues!?!Please help!!!

So about 3 days ago i took a digital test way to early . It of course was negitive.(i ovulated around the 17 af due 30th) so i threw the test in my normal spot in the bathroom by the sink. Then today while i was doing my annual look over my old test ,to see how often i get evaps, it says yes with the little clock. I am super confused now. I thought after 30 min. The screen would be blank . I would retest but my husband hid all my test so i cant till the 30th. Has this happened to any one else????