Clank, and grinding.
 

I have a Diamondback Groove, pretty new. I feel a grinding feeling when riding, and sometimes, when in low gears, an high, It makes a Clunk noise, don't know what this could be...SORRY if this is not detailed enough, if you could ask questions, I shall do whatever I can to help! Sorry again. But I'm a newbie with bikes, an I was just wondering.

There's not much detail here so I can't point you in any direction, but your drive train should be quiet and smooth with hardly a peep except during shifting.

You might need to oil your chain, adjust the trim of your derailleurs, tighten the cranks, adjust the bottom bracket, or any number of things, or it may really be nothing after all. Since your knowledge is limited and the bike is fairly new, I suggest you bring it to the local shop and have them take a look, or even a test ride, and correct the problem if any, or at least reassure you that it's OK.