if i am pregnant around when would it of happened?

Amber
In August I started spotting around the 22nd for only a couple of days, the spotting stopped, I took a home pregnancy test on August 26th that confirmed i was pregnant, i then started spotting up until September 7th. I was told by a doctor on September 3rd that my HCG. levels were going down and that i had lost the baby but they did not give me any time frame of what date this could of happened. My last actual period was July 9th to the 15th. could part of my bleeding in September been a period if not shouldn't I of had one by now it has almost been a month since i lost the baby? We were not really expecting to be pregnant with the one we just lost, and right now definitely is not the best timing. I am scared to take a test but also am wondering if i am around what date could conception of occurred?