Are There Pregnancy Symptoms Before Implantation?

Not physical symptoms, no. By that I mean, the symptoms that HCG produce. Like morning sickness, sore breasts, fatigue, etc. There is a phenomena, where woman feel these symptoms right after they have sex, before they implant, and other similar scenarios. These are generally woman who want to be, desire, or are trying to get pregnant. Those would be psychological symptoms, that manifest psychically. (I'm not saying the woman would be crazy, but that our minds convince us of what we want. It's very well documented.)

No - as bug explained, any "symptoms" are psychosomatic. Until the embryo burrows into the uterine wall, the body has no way of knowing that there is a fertilized embryo in there. Many of the "symptoms" are really the same thing a woman goes through every month between ovulation and her period, it's just that most of us don't notice them. The only two times I was aware of the possibility of pregnancy before a missed period were my two IVF cycles, and I remember paying attention to every single "sign" but had to admit to myself that it felt no different from my period coming on. The second cycle was the one that took and I definitely felt a little pregnant 10 days after the embryo transfer, but that was more of "I have a really strong hunch that this is it" than anything physical.

I think so...I knew that something was up when I got pregnant with my daughter. My back was hurting and I was bloated. I was 2 weeks from my next period and I took a pregnancy test and it came up positive.

Honestly, I was throwing up for two weeks before I was supposedly pregnant. I think my due date was off though. I think a lot of people are prego before they realize it so the symptoms are still really after implantation.

It's possible, because with my 3rd child I had morning sickness a week before my period was due, and that is still within that 12 day window.
At any rate, I think the God who orchestrated creation and all these amazing processes in our bodies might have created a way for our bodies to know we are pregnant before any scientific test could tell us we are pregnant. Just a thought though...
But I'd still like to ask him why we have to have such brutal morning sickness sometimes :)

Ha- I knew I was pregnant by the second day. My husband made fun of me until I got a postive test result a week BEFORE my period was due to arrive. I think my HCG levels rose very quickly. Also- if you are doing charting with temperatures- you can tell within a day- because your temp will rise instead of fall after ovulation. In my experience, this was a very obvious change from previous cycles I had charted in which I did not get preggo. Best of luck!