Faint charting question

Renee • 34 with 3 babies; 15,10&8. 2 angels 8/15, 3/16
Do you chart a positive in your data if it is faint or you are unsure it is for sure bfp? Or do you wait for a solid bfp to record it?
I took a hpt after work today because I thought earlier in the week I had a faint bfp.  I forgot to check it on time and then when I just went back in the bathroom it had a faint line. 
I know I'm not supposed to read it after 10 min. And will test with fmu tomorrow. What do you think? Should I log it bfp or bfn? (I think keep it bfn til I double check tomorrow but curious of others thoughts)