Ramya, FF may not always be right. It changes the 'O' date as and when we enter information. So unless it was a very clear shift, you may have actually ovulated later and the cramps may mean ovulation cramps as well (very few women experience this)
I say this because you have mentioned watery discharge which is considered fertile...Usually CM changes texture the same day or the day following ovulation and is no more egg white / watery..
While it is unlikely that it could have been implantation at 3dpo, nothing is impossible and each woman is different! So good luck
Vasumathy, wow, cramps at 9 dpo sounds great! Fingers crossed for you. Do keep us updated. Good luck!