opk and pregnancy symptoms

So I had a miscarriage on 13th November and did opks all this month and nothing until my 26th day of my cycle Saturday I had a smiley for one day on clear blue digital now gone back to nothing nomperiod but my boobs are killing me I'm so tired hungry feel sick and full of cold...is there any chance my one smiley could of bee hgc or would they of continued I had a negative pregnancy test yesterday but it was a digital and I know they require a lot more hgc and I don't know when I would have ad if I've had late ovulation so I'm not sure if it's all just in my head now??help???