Is medical marijuana what we think it is?

I recently purchased medical marijuana.
However, I am not able to smoke it. It makes me cough violently, it is as if my body fights it with all his strength.

I smoke cigarettes, no problem. And even though I never was a recreational user, I did smoke some weed back in the days and never had any problems.

It makes me wonder...

Could it be that the new, improved and legal marijuana has, lets say, some properties removed and some added? It IS genetically modified I assume...

I'd appreciate any thoughts about this subject...