Problem with BBT??

Bryanne • I`m 24 years old. Been together with my fiance for 6.5 years. We have a 4 year old son and TTC #2, hopefully ASAP!! Baby dust to all!!
We're on 13 mos of TTC. We ended up having a miscarriage (5wks) at end on February and had a normal cycle in March. Were back to trying again and this has been my first time charting since the miscarriage. Now it seems like my temps are all messed up. Any advice or other experiences would be great to hear. TIA.