coffee enemas are not considered for parasites, but they do stimulate the liver to purge. I did get out worms doing them, but it wasn't the Coffee-Enema that killed them, I had been cleansing and it just helped get them out. ACV also helped, and got out alot of filmy stuff also.
You really should not have pain when you do an enema, I'm not sure what that means.
It is possible that your nausea is caused by blockages in your small intestine, which could be parasites. If you are not constipated, you might want to try some psyllium to see if you can push stuff out, it will make your detox go faster also. Keep cleansing and good luck, hope you feel better soon.