I'm 19, had my first baby June 2007 every thing went smoothly found out I was pregnant on day one of my missed period. Now I am 8 weeks late coming on my period, I am always regular, I have symptoms like feeling tired throughout the day, sore breasts, weight gain but the home tests are all negative?

If your period is eight weeks later (so you could possibly be ten weeks pregnant), I'd go to the doctor or maternity hospital and ask for a full test and possibly an ultrasound.

Weight gain is not an indicator, in fact many women lose weight in the first couple of months, and there are other things which cause cause tiredness etc, but I think you should get checked out.