Does this mean you lost all your data?
Often a hard drive that will not boot can still have the data easily recovered. After installing a new HDD simply connect the old HDD via USB adapter cable, they do not cost a lot. Ask geeky friends if they have one. If you can access it you can copy the data to new HDD. Only way to find out is to try it. In most cases the data is still there, it is a corrupt boot sector or system file.
If data is not important try reinstalling the OS. This will wipe out all data. If the issue was an unexpected shutdown the HDD could still be fine. Many manufacturers have built in diagnostics you can run to test the HDD from the BIOS.