Symptoms of a bad head gasket help 😞 Options

[Oreo20]

I have a 94 Celica gt with 172,xxx miles
Today leaving from work on the high way my co workers said they could see white smoke
Coming from my muffler so they told me to accelerate and every time I did white smoke would come out .
Car was warmed for 2 mins and outside temp was at 64
Car still read cold takes for ever I know I've had it like that for 3 years since I got it
I got home and checked oil it was good no creamy look
Put a camera behind muffler reved it hard and no smoke or water .
Radiator coolant still all the way up
But I did see it was fuller than I remember
Not sure what sweet muffler smoke smells like
Can anyone tell me what's wrong
And what I can do ?