Can I regain information after erasing data using Find my iPhone?

As a joke, some kid set a passcode on my iPhone that I do not know. He apparently entered it wrong, because he was unable to unlock my phone after setting the unknown passcode. I'm absolutely livid. I now need to restore my phone because I can't get into it because no one knows the passcode. So I went to back it up, and it told my that it couldn't back up because there was a passcode. Okay. If I didn't have a passcode I wouldn't really need to back up, but okay, whatever, I just want my phone back. So I try to restore. Nope. "iPhone can't be restored because Find my iPhone is turned on. Please turn off Find my iPhone in settings on your device." BUT I CAN't UNLOCK MY DEVICE. Way to go, Apple. Thank you. Then I went to icloud.com to remove my device from Find my iPhone. Well, turns out I can't do that either without unlocking my device. Did Apple ever even consider the people who get locked out of their phones? This is beyond absurd. So now, the only thing to do seems like to do the "Remote Erase" on icloud.com.

TL;DR: My main question is, will I be able to get all my stuff back on my phone after erasing with Find my iPhone? Can I get any of it? More importantly, does erasing with Find my iPhone also erase the data from iCloud, or can I sync with that after erasing? I'm so distraught over the thought of losing all my apps and pictures.

Also, I can't take my phone to any Apple store or get any support from Apple because my phone is jailbroken.

Without the passcode, your phone is a "brick", meaning it's as useful as a brick to you. Your only option is to get the passcode.

If you have stuff backed up to iCloud, you can get a new iPhone and log in with your Apple ID and it will restore the contents in your iCloud. To check what is in your iCloud, go to iCloud.com.