Bleeding in the middle of the month, can it be a sign of pregnancy?

I want to take a doubt, my menstruation came down on 5/4/2012 and stopped on 10/4/2012 more when it was 19/04/2012 began a slight bleeding I believe that this day was in my fertile day, it may be a sign of pregnancy or not, please respond.
Expert answer:

Perhaps. If it was related 1 or 2 days before that, maybe it could be a nesting signal (but it's a lot of highly speculative guess ...).

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