Charting Newbie HELP

I’m 4 DPO and received my BBT the other day in the mail. The morning I didn’t test was because I worked overnight.

Since I have a sporadic work schedule where 1-2 mornings I am not here will my chart still be accurate ?

Today I’m 4 DPO and temp was 98.4… I am not sure if that’s good or bad or irrelevant. I just want to know what to look for to see if I did in fact conceive. Oh and I ovulated CD14