Bigbang According To Roger Penrose
Reverse bigbang cannot be interpreted from the verse you mentioned. No Quran donot tell any creation of universe before this one. Conformal cyclic cosmology model simulation havent been consistent in their results. Hence, not accepted by wide cosmologist community . Entertaining such ideas by non-cosmologist should be avoided for now.
Well I think and I am not sure what Islam says about it but in my view qayamt is only for Earth and not for the whole universe. only the earth will be destroyed by the destruction of the Sun so Qayamt means most likely the destruction of our Solar system. Because most of the destruction mentioned in Quran which will happen on the doomsday is the same as depicted by different scientific literature when our Sun is destroyed either by to become black hole or dwarf. The rest of the Universe will be preserved and It will most likely continue to expand unless there is a temperature death of the universe. I don’t know what will happen then.