Your chart looks anovulatory, meaning it doesn't look like you ovulate. I looked at your other charts too and it doesn't seem like you consistently ovulate.
That would explain the erratic temps.
The first half of your cycle (follicular phase) is controlled by estrogen, the cooling hormone. This explains why the first half of your cycle means your temps are lower.
The second half (luteal phase) is controlled by Progesterone...the warming hormone...this is the hormone that is responsible for the increased temps after O. It is secreted by the Corpus Luteum that has formed in the space the egg was released from...this hormone maintains a pregnancy. If pregnancy doesn't happen the temps go down, and progesterone slowly goes away for AF's arrival.
So with that being said, have you thought about doing a female hormone panel (blood or saliva- saliva is better for you bc the blood draw is best on CD-19-23 and since you don't ovulate you probably have erratic cycles as well.)
This can be easily fixed! assuming of course there is not a greater underlying issue (which in most cases there's not!)
Hope that helps!!!!