Hi Tracy
Are your periods normaly regular and this one was different? The reason I'm asking is that my periods are usually regular, but about 3 times I've had periods or light bleeds after about 13/14 days after my AF. I didn't go to the Docs, but from looking on the internet there were a few reasons such as implantation bleeding, a sign that ovulation had occured or an infection, along with lots more reasons. What I would do if you do have regular cycles, is carry on TTC as normal and monitor your periods over the next month or 2. If they are still irregular then go to your docs and ask to get checked out.
If you are having irregular cycles then keep on at your docs to carry out tests, or put you on a regulating medicaion, as you are TTC and every month counts. I'm not too sure of all the info on irregular cycles and could be wrong, but there is a TTC with irregular cycles thread in the TTC section.
Hope this helps and good luck TTC x