When buying a house became a nightmare

I bought a property and got it on the 20/06/15. I moved in on the 21/06/15. We found many defects that were not disclosed by the seller and this upset me greatly as it would have greatly affected my offer. More importantly my dad an uncle noticed electrical and plumbing concerns and they questioned how the property could be passed. Namely there was no earth spike, no stop cork, there was a leaking pipe in the bathroom, exposed wires etc. That very night the pipe started leaking and we called on a plumber to check it out. He said that the leak was coming from a pipe in the wall and that the plumber who passed the house must be contacted via the agent. I didn't know this as the agent never said that we should contact her for problems, being a first time home owner. He temporarily stopped the leak to prevent the house from flooding through the night. The following day the electrician and plumber came with the agent and the plumber Keaton denied everything. He insisted that there's a stop cork but could not show anyone. He was called again when my dad was here and agreed fix the problems. It's the 27/06/15 the leak has not been fixed. I'm back and forth with the agent but no luck.