If your temp stays elevated beyond the 14-15 day normal Lp, it would be a good indication of pg. Not a guarantee, though.
After ovulation it normally goes up and it drops right before your period. I can also drop in the middle of your cycle or even around the implantation - it is called the implantation dip.
My cycle is 26 days and I guess my lut.phase is 14-15 days? Because I think I ovulated on day 11 or 12 this month.
Most women will see a drop in temp just b4 af arrives. I am an exception to the rule, usually see a drop a day or 2 after she shows. How long is you Lp normally?
I think that your temp goes up....and will stay up until your period...I was told by the gyno if it stays elevated for more than 18 days to take a test.....but you need to test at the same time every day......hope that helps