can you get a positive OPK after ovulation?

Rebecca • 27, TTC my second baby. I love my husband for giving me baby #1 who is the most amazing gift in the world!!
So I need one more high temp for FF to confirm ovulation which would have been on CD18. From CD17 to CD19 I had super strong positives that's strong test line showed before control line. Today CD20 it is still positive but not as strong as before. Could it be I had a very long surge and it's still detecting them? I will upload my chart. First OPK is from CD17 to CD19 and second one is from today CD20. I just had a glob of snot like cm, had the consistency of EWCM but was milky white colour.