Hello, im a newbie to vaping, just recently bought my istick pico+cubis pro. i used to smoke 15~ cigs a day. the first e-juice i got is a 6mg nic -basically what the shop owner told me to get based on my nic needs- currently vaping 0.6 ohms @ 18watts, MTL. but the lung hit i sometimes get is unbearable. what adjustments should i make?