Well, I took Pepper to the vet yesterday. I got him weighed and he was 390g, which sounded like a healthy weight to me. Anyways, the vet came in and asked me some questions, and then he used a cotton swab type thing to get some skin cells from Pepper's skin. He then put it on a slide and looked at it under a microscope, but found nothing out of the ordinary. So next, he did a skin scraping. I decided against using drugs to keep him calm (I don't remember what its called, but it would've costed a lot extra). So the vet was holding him and trying to move the quills out of the way to get a good spot to use the blade on, but he got impatient and decided to pull out some of Pepper's quills! I couldn't bear to watch, I knew he must have been in pain, and I almost started crying at the sight of it. Anyways, he did the skin scraping, but still found nothing. He said the next step would be to do another VERY expensive test and send it in to a Michigan University, but he suspected that all Pepper had was a "vitamin c deficiency", which just means he wasn't getting enough fruits and vegetables.
In conclusion, I really wish I would've knew that before I spent $70 to find that out! But it's better to be safe than sorry. Thanks to everyone who tried to help out here =)