Lysine makes me tired

I remember taking Lysine a few years back to treat cold sores and it made me feel very fatigued so I stopped. I had another cold sore outbreak recently and a friend gave me some Lysine, 1000 mg. The next day I felt like shit. I did have a smaller, shorter outbreak, though, but I don't know if it was attributable to the Lysine. (I also tried coconut oil)

So, does this happen to anyone else?

I have read on the internet that lysine and arginine compete. But the arginine amino acid must be used by your body for something, right? Can reducing it too much have a negative effect?

It makes me wonder if the people taking it as a daily supplement are actually doing something bad to their bodies in the long run. I don't know. Personally, I think maintaining a more alkaline pH is the way to go.