Full HardDrive Cleaned Important data lost - Hp Laptop

Hi Everyone,

Today was a bad day for me as i lost every single file in my Hp laptop. I think it is all my mistake. let me explain what happend.

My laptop have 500GB HD. Laptop came up with 456GB of "C" Drive partition. Other 3 paritions were HP_Tools, Recovery and System.

"C" drive was half full when i decided to divide it into more drives to save important data from "C" to another drive. After searching on internet i came to know that windows 7 has a limit of 4 parititons. then i started searching for a quick solution to avoid full new windows installation. I installed a Mini Tool Parition manager and Set the "C" drive as Logical and shrinked more drives from C. Computer restarted Partition manager takes 10 minutes to do everything and then WIndows started and all was ok. But I wanted to have one more 100 gb partition from "C". I did it again using Parition manager and computer started all stuff was going well. Parition manager finshed everything and when computer restart nothing works. Every time computer restart from windows 7 Logo. I was sure that something goes wrong. i tried to repair it but repair takes 30 minutes and solved nothing for me. i canceled repair and try to install fresh windows 7. when i was selecting the "C" disk to install windows in it. An error appeas saying "windows could not format a partition on disk 0. The error occurred while preparing the partition selected for installation. Error code."
nothing was helpful. I then run these commands "Boot into the install/repair disc and wait for it to load
Choose “Repair my computer”
Select “Command Prompt”

Type diskpart and press enter.
Enter list disk and note the number of the disk you want to install on.
Enter select disk n n is the number of the disk.
Enter list partition and note the number of the partition you want to install on.
Enter select partition n n is the number of the partition.
Enter active
You can now close the command prompt and re-attempt installation."

and again it was some kind of error. At last i select parition 0 and clean all. and closed the command. When i restart the computer it says "no bootable device insert boot disk and press any key"
it was again very frustating. then i plugged in the USB of bootable windows 7. it was started smoothly and when i reached the partition selection window it was all cleaned. Only single harddrive of 456gb was showing. everything is cleaned. There was too important files in the hard drive. I have made a big mistake. I need expert help. Please help me recovering the data. Thank you in advance

@SIW2 I admit it was all my mistakes. I Don't know too much about hardware things. I was very tense about data when i ran clean all command. I was hoping for good and did'nt understand what the command will do for me. I am admiting my misktake. I will make a backup first in future but today i made a mistake which cannot be undo. Now i am hoping is there a way to get some data back? thank you

I strongly recommend Lazesoft for Data Recovery
Lazesoft Recovery Suite Home Free Download
It runs under Windows and can create a Boot Recovery CD that uses WinPE.

Two appalling errors in your first post.

1.
There is no limit of 4 partitions in an version of Windows.
I have 8 partitions on one Disk.
MBR Disks are able to support up to 4 "Primary Partition" per Disk - or 3 "Primary Partitions" plus many "Logical Drives".
GPT Disks provide many more "Primary Partitions".

2.
You cannot boot into a Logical Drive, You can only boot into a "Primary Partition".
HOWEVER if you are booting into "System Reserved" on a "Primary Partition",
then I guess that may safely transfer control to C:\ in a "Logical Drive",
but that is a "step into the unknown" which I would avoid if possible.

Regards
Alan