am I gonna have my period soon?

over 4 months postpartum and breast feeding. I do feed my daughter formula when she's being babysat by grandparents since I'm at work and unable to breast feed her. because of this my doctor told me at my 6 week check up that I would have my period start sooner than if I was just breast feeding. but it still hasn't came. I noticed just now that I'm starting to get an egg white texture cm (which I haven't had at all since...well since before I got pregnant) so I was wondering if this could be a sign that I might get my period soon?