Car overheats

My car is overheating. It will go from the halfway
mark on the temp gauge to the top in just seconds.
As soon as the indicators go off beeping to tell me
the "engine is hot turn off a/c" i pull over and shut
off engine, so its not being drove while hot but for
less than 2-5mins to safely pull over. When driving
down the highway it drives ok as long as the a/c
and air recirrulator are not going but once in town
stop lights, stop signs and traffic make it overheat.
I have no other vehicle so i have no choice but to
drive it approximately 15 mins to work and back
but other that time its been parked. When it over
heated the first time it wasnt low on coolant but
there was sroom to add some, no problems after
that until now ( a month later). I have always been
very cautious with the fluids. There is always
coolant and oil is always tapped off. When it over
heated 5 days ago the change oil indicator went
from 83% to 0%. The towing company i used said
that it was just a safety feature it did that? I had
just changed the oil 2 weeks prior. He reset the oil
indicator and changed the coolant tank sensor and
thermostat......still overheating. Check engine light
came on and he said it was showing it was in limp
mode? He reset that. (Its stayed off since). 2 days
after being stranded it overheated again, this time
not as hot but now when starting the engine it has
a gurgling sound and then when beginning to drive
has some clanking sounds that after getting on the
highway stop. When i first bought the car 6months
ago previous owners had NO issues (family
friends). It started and turned off very quietly, when
turning it off it sounds rough now.  A friends
husband looked at it and said there was
condensation coming from the exhaust............i
dont know what else could be wrong......im a single
mom on a very tight budget.....this is my only
rig......any ideas???