Hi Guys

I'm a beginner so excuse my ignorance. I was wondering what the difference was between getting a distortion pedal and upping the gain on my amp?

Is it a completely different kind of distortion?

The thing that bugs me is that at low volumes the gain on my amp doesn't sound great, will it sound better at lower volumes with a dedicated pedal?

You are probably not getting much help because your question is somewhat incomplete. That is to say, we need to know what amp, guitar, etc. you have first. We also need to know what genre of music you are trying to play. See what I mean? Give a little more detail and we will all be glad to help

when u turn up the gain the sound goes up thus distorting the sound.when u use a pedal u get a "clean" Distortion

gain on an amp is like a really high overdrive. pedals like a Boss DS1 *i hear it sucks* is a distortion pedal.
Okay, lets get some things straight here. What amp do you have? And heres how it works. Overdrive is used to push your amp into distortion. Its lower gain and and smoother. Distortion is more abrupt and aggressive (And often higher gain) then over drive. Over drive is often used as a lead boost over an already distorted amp, while distortion pedals are almost always used over an amps clean channel. Your gain knob on your amp controls the amount of distortion the amp itself makes. Most people buy OD/Distortion pedals for a different sound or boost. A common noob mistake is throwing a dozen OD pedals in front of a crappy amp rather then buy a new amp.

EDIT: I should add an OD pedal may help your issues with it not sounding good at low volume, but I can't say for sure until I know what amp you're using or if its tube or solid state.