Ah, it hurts me to hear you say that man! Penis Enlargement is not just about making gains every time you look at your penis. It's a learning experience. The past 5 weeks you've learned some things that are going to help you for the rest of your Penis Enlargement career. Don't expect constant, consistent gains.
Now, when you measure is the most important aspect of measuring girth. You are probably like me, measuring a ton. I measure 10-12 times a day. Even so, I take EVERY SINGLE MEASUREMENT with a grain a salt. Over time though, you notice trends. The lowest measurements aren't as low as they use to be, etc. I know it feels like you have to have a solid measurement to see if you indeed have made gains, but I've learned that it's hard to get a true, accurate measurement. Measuring trends is where it's at.
Otherwise, if you have to have a single measurement, I recommend doing this. Wait 48 hours after your last workout. It sounds like a while, but it is really just measuring before your first routine on the day after a rest day. Edge for 5 or 10 minutes, and you will be at your maximum erection level. Measure in the SAME PLACE. If your shaft is inconsistent with girth, measure 3 inches up the shaft, and measure there, every time.
If you notice you are indeed not gaining, give your routine a thourough look see. You may need to increase or decrease the intensity, depending on your situation.
Good luck guy, don't give up. Absolutely no part of Penis Enlargement is in vain.