Well, were officially trying for our 3rd. i want to do basal temp charting... i BF my 1.5 yr old once or twice through the night..will this effect my temp?
and do i just place the basal therm under my tongue like a normal therm?
Yes it will make a difference and correct it goes under your tongue.
BFing may or may not effect your temps. Some women only need a few solid hours of sleep for their BBT to be accurate. I would be sure to temp at the same time every morning and make note of how many hours of sleep you got before temping. You may find that it doesn't make a difference. I can get as little as 3 hrs of sleep and still get a pretty accurate temp.