How to measure EQ

Is there any way I can objectively measure the quality of my erections? The other night I thought I had a solid erection during sex and my girl asked me why I wasn’t hard. I feel like I am limp and don’t even realize it! I want to see if I am adequately stiff the next time I masturbate. Any tests or anything I can do?

Starting size: 6.5 BPEL 5.1 MSEG

Goal size: 7.6 BPEL 5.6 MSEG