OPK positive...?

So I have super random periods like weeks to months between and I just randomly take OPKs just for my own curiosity. Well tonight (like 12:45AM) I took one just to see what it said because I was having cramping in my ovaries and it came out positive. Now I'm very new to tracking my periods and ovulation and all that so I don't know if maybe somehow I got a false positive or what because according to my chart I'm supposed to have AF on the 6th...could this be right? The bottom 2 tests are random ones I've done over the past couple weeks and the top one was from tonight. Any help would be nice. Thanks!!