Clomid and opk help

Beth
So I took clomid days 5-9 of cycle. On days 13 & 14 my cervix was high and soft but opks were neg. The opks were close but def neg. Yesterday, CD 15, def neg opk. The opks on 13 & 14 were extremely darker than CD 15. Today, cd 16, I got a def pos opk. Has this happened to any one else? Could I have had diluted urine?? I'm happy I have a pos but confused as to why I would get darker test lines then practically nothing to a pos. Just strange. Also, hubby and I bd on cd 13 & 15. However, he did have a fever yesterday. Any thoughts and info welcomed.