question about meters begin different.

Hi. New to this whole thing. I got diagnosed with type 2 diabetes about 2 years ago and doing good with the whole diet change, kinda. I'm figuring out a lot of things since also on medicated for my ADHD.
I went and bout another glucose monitor to keep in my purse, if I move my home one I will forget it and then just never take my blood sugar.
I bought the same one I have, contour next one if that matters, at home. I just opened it and was like lets test it. First test was like 20 off, my old one said 160 new one said 185. I'm like ok i poked 2 different fingers lets do the same one. so second test was old 172 and new one was 163.....
I'm not concerned with the numbers as I ate so its fine. its the differences that get me.
I tried googling it and either I'm not wording it right, which could be the case, cause all I got was see your doctor.
Is there a reason they would be so different? should I be concerned?

Thanks for any help. I'm trying to do better and since getting my mental under control I have been better for this.