Unfortunately, there are is no way of telling if your TB-500 is legit as there are no side effects associated with it... Healing also takes time and you can't be sure that it's working.
Have you used Ipamorelin before? It is the weakest of all GHRP's in terms of GH release. For me, Ipamorelin doesn't give any flushing side effect while GHRP-6 and GHRP-2 does.