The guy needs help on properly filling his cartomizer with juice, and you guys are recommending different mods to get or telling him how he needs to set up an RBA and telling him about mechanical mods and batteries. He never asked about those. Do you even read what the OP asks?
wtbcody - the most important thing to learn about
cartomizers is to properly fill them the first time. I have a strong hunch that 15 - 20 drops was not nearly enough juice. It tastes miserable because you are attempting to vape a essentially dry cartomizer. Unfortunately, that carto is probably ruined now. Once a carto's filler is burnt, you'll never get that taste out of it. Start over with a new one.

click to enlarge
Above is a cut away of a cartomizer. (Disregard the red arrow outside the carto)
Cartomizers or carto's are steel tubes filled with polyfiber that looks like a cigarette filter. A heating coil within this material heats e-liquid into vapor. A small air tube in the center of the filler runs its entire length which directs vapor into a drip tip placed on the end. The drip tip is just the name vapors use for a mouth piece.
Single coil cartomizers have one heating element, dual coil cartomizers have two. Heating coils have a ohm or resistance rating, which determines the amount of energy used to heat e-liquid and turn it into vapor. A drawback to using a cartomizer is being unable to see your juice level. Cartomizers can be used alone, or be used in a cartotank which allows larger quantities of juice. Since these tanks are often clear, you can see the juice level in them.
Before you add liquid to the carto, use this tip. Plug the center air hole with a toothpic. You don't want any e-liquid getting in that hole. When the carto's filler looks wet, shake it down like a thermometer. Then add more e-liquid. Shake it down again. Repeat this drip-n-flip technique until the filler will absolutely hold no more liquid. It should look like a slushy drink when ready.
You'll need to add additional liquid after a period of time. It's tough to know when, so top it off frequently at first so that you don't burn the filler again. After vaping a few drags, the top of the carto will always look dry - that's normal. You should be able to repeatedly refill the carto multiple times. Once it gets a stiff pull when you vape, it's time to replace it.