Engine Cooling problem
2000 Dodge Neon 4 cyl Four Wheel Drive Automatic 193,00 miles

I live in new york city just got a dodge neon to get be back and forth to work car worked good in the summer time now it started to over heat took it to a mechanic he did a coolant flush and put in new thermostat when i was driving home car over heated again took it back now he said i need new head gasket and water pump timing belt because the car giving a burning smell i took it to another mechanic he said its not the head gasket if so then white smoke would be coming from my car he said the fan is working but maybe the cooling fan censer is having the fan starting late and i may need a radiator cap poss a leak somewhere because the car was running for awhile and didnt over heat only when i was on the highway please help i dont no which mechanic to trust

is there any white smoke/steam coming out the exhaust ?? doesn't have to be clouds of smoke .. just a slight white smokin .. is there any muddy chocalatey deposits on the oil filler cap and or coolant filler cap .. do you see muudy gunge in your coolant bottle if there is any of these then your head gasket hase gone ... when replacin head gasket you have to remove timing belt .. so may as well renew it at same time .. if it snaps later its more $$ .. i can't comment on the pump ??