Toyota Repair: camry water pump, hydrocarbon emissions, coolant leak

Question
i have 90 camry dx 2.5 v6 2wd at 164000 miles. A few days ago when i started my car it was running very rough,the whole car was vibrating,not running smooth. I drove it a block or two and all of the sudden fine and smooth again. it did it again the next day. same thing,then it just stopped. only happens on first start of the day. The third day it did not stop,it was hard to accel, hard to hold speed, running rough, bad vibrations, then overheats and loses most of antifreeze out the overflow.I only drove it 10 miles .I tried to crank the heat to aid in cooling but it only blew out cool air. I have pulled the temp. sensor housing and found it to be dry.The top radiator hose was dry too. now when I got the thermostat off there was still fluid behind it.I think that the water pump is failing. Would that make it run rough and overheat like i described?and do you know a quick way to verify it's failure. also is it poss. for anti-freeze to work its way into the heads via the timing belt compartment.my car has 164000 miles and is in need of valve cover gaskets.not pouring oil but a slow weep that absorbs dirt looks cruddy The timing belt was done at 60 000 and is due. I would welcome any insight you have into my 2VZ-FE problem.  

Answer
Thr engine overheating may have caused a headgasket to start leaking causing the rough running condition, there are two problems,the overheating problem and the possible headgasket failure, at this point I would have it checked for a possible blown headgsket, the best way is to have it checked with an emission control analyzer, it can read hydrocarbon emissions at the radiator filler neck with the engine running, try to find someone that can do this test, the toyota dealer is a good place to go for this.
If the headgasket test shows there is no problem find out why the engine is overheating, maybe it's just a failing thermostat, there could be aproblem with the radiator or there may be a coolant leak.