Running problems

HI

I have had my 00 V Focus 1.8 Zetec for almost 2months and theres been something wrong every 5 mins. I posted earlier with a power steering leak i think this is now the least of my problems with the car. I checked the fluids after going for a run to notice murky stuff on top of the coolant in the reservoir. And there was also a slight bubling. I checked the oil cap and there's no milky residue. Also checked dipstick which also appears ok.And stopped the car for bout 20 mins. I wouldnt say the reservoir was over pressurised. It wasnt trying to fly through the cap. Like it would if there was a leak of exhaust gases. I also smelt inside the reservoir the was no smell of exhaust gases being used to checking for this having previously owned a Rover 214. It didnt smell like oil either. Ive been just out checking the car over again. There's not any coolant loss. I did however notice that there is a hose from the reservoir to the air conditioner. Is there any oil or anything that could be getting from the air conditioner to the coolant? There doesnt appear to be any running problems or abnormal smoke from the exhaust.

I hope this is not hgf!!!

Any help would be great before i go anoying my local mechanic lol!!