Glucose Meter Readings

Hello! So I am prediabetic. My A1C is 5.8 and my insulin is at 34. I was using a Stelo CGM and my sugar levels were going crazy into the 170s. I think it was the device and the placement. I’ve now been using a regular CVS brand glucose meter. The other day I didn’t think I got enough blood so I tested again. And again. Then I spiraled:

157 119 134 125

My question is. Am I to trust the first reading I get on glucometers?

Thanks in advance!