Frozen Engine?

I dont think there is any antifreeze in my engine because ive only been topping up with water all year.
today when i started it up it struggled to start...then it would only blow cold air. 10 mins into driving it, it started over heating the temp gauge went right to the top and stem coming out of the bonnet.
Any way i stopped the car the water was bubbling in the plastic tank....I left it all day went back bout 6 hours later and the water tank was empty...i poured some antifreeze ready mixed into it...then some water....I started it up and the temp neddle stayed normal and the heaters were nice and toasy. I drove bout 6 miles home then i poured concentrated antifreeze in the plastc tank bout 1L. My question is this...
Will my car be ok now? Ive put a thick blanket on the engine tonight under the bonnet....Please if anyone knows...will you tell me!