1989 Oldsmobile Cutlass Low Coolant light and temp light co

Heater problem
1989 Oldsmobile Cutlass Engine Size unknown Two Wheel Drive Automatic 115000 miles

My Low Coolant Light has been coming on for the past few weeks, we believed it was a bad sensor. Yesterday it came on and stayed on the 30 min compute home as well the Temp light came on and off for about 10 mins. I turned on the heater full blast, the temp light went out, then a few mins later it came back on and the heater was no longer hot it was blowing cold air. When the Temp light went off the heater blew warm air again. This continued for the rest of the drive home. There also was a faint smell of antifreeze. There was not any antifreeze on the ground.

Thank you for your help
Jenn