No positive opk but bbt temp shift

So we went on vacation during my predicted fertility window which was great. I was checking cm, bbt and opk. Cm was eggwhite for almost the whole 5 days but I never got a positive opk. I was only able to test once a day in the mornings (which is what I normally do at home) but never got a positive. I did however have a big spike in bbt but it was a little later than I expected. Does bbt spike indicate for sure I ovulated? Did my body get thrown off from travel/time change etc? Help! TTC. the chart is reflecting a later ovulation because I was putting in the negatives so it kept shifting the ovulation date further but I have a 25-26 day cycle.