Oil and water together

I've been pinning winny and test separately for about 8 days. Wednesday I put both in the same syringe and injected into my quad. Everything went good. Injecting slowly to make sure the winny didn't shoot out. It was a little sore but today it's real sore. Could it be from mixing the two into one injection. Has anyone had an experience like this? I'm not sure I will try it again. It was difficult to get an accurate measurement when extracting the two into one barrel given the nature of oil and water.