NTA

I'm 98% certain the professor knows exactly what they are doing. There's a number of reasons this could be happening: You don't understand exactly how the grading system works (for instance she's grading out of 88 points instead of 100, you could earn 71 points but that would be 80% of the total points available). You misunderstood exactly how the syllabi and grading is laid out. The automatic system adjusts to reflect overall percentage without weighting scores correctly. She is curving through some weird system where it's not a traditional bell curve, so she doesn't consider it curving. When she grades a test, she sees where the common mistakes are and add points evenly across the class to correct for that. (ie: Everyone got 10c wrong the same way, I must have written a bad question, I'll give everyone 3 points to make up for it). With a class size of less than 10, she's got some weird rubrics that she's applying non-transparently. And yes, she may be sympathetic to your situation and making some judgement calls about how harshly she grades you specifically. Most grading is a least a little subjective, and students are fooling themselves if they don't think their behavior reflects the way their professors regard their work.

The point is: It happens, it's not your fault, and you are not cheating. You can ask for an appointment where she can explicitly explain your scores and what you need to finish the class successfully, but I wouldn't rock the boat. The only case where I would do that for this situation specifically is if you were afraid you might be failing the class because you don't understand the grading. For instance, you need a B to continue with the program, but you have one class average that is in the 70s and one in the 80s and you need to know which is correct.