Hello, I recently bought an Njoy ecig with 2 cartriges in an attempt to quit smoking. A couple hours ago I finished my last pack of cigarettes and I tried the ecig. I took 4 puffs and my heart felt like it was going to jump out of my chest. The two cartridges combined are supposed to be equal to 300 puffs. I want these to last as long as possible because it costed 20.00 dollars for the ecigs and cartridges, but I also want to feel satisfied so I don't start smoking again. Does anyone have any suggestions or guidelines?