Find a high quality whey protein isolate that is free of artificial sweetners. I can't help you out on a brand, I use all Canadian made supplements. The US is bit behind Canada in terms of organic, clean nutrition and sports products and supplements.
I am familiar with NO-Xplode but have never tried it. I stay away from stimulants of any kind, don't even drink caffeine. It is strong stuff - I highly doubt what you are feeling is placebo. I think if I took NO I would be too shaky and edgy. I know quite a few people that swear by it, and love it. If you like it use it. It
does contain caffeine. It also is full of artificial sweetners/flavours, chemicals and dyes.
http://www.befit.ca/noxplode.html
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