overwriting some files in git remote

I am using git and apparently I screwed something up.

So, I have my local PC (called A), then my local PC (called B), and my remote.

After a series of of events (forgot to pull stuff, and then worked locally and so on) the situation goes like this :

• remote has a copy
• both of my local files have different changes
• in the last week I have been making changes from local PC B. So local PC A has rev 2 let's say, and local PC B has rev 11 (latest of server) but both of them have different local changes

On my attempt to see what to do, I made things even worse.

• I pushed data from local PC A (maybe forcing it - I am not sure)

But these removed all my other changes. I don't know how I managed that.

Not only that, but all my commits made from PC B (rev 3 to 11) lets say are gone from history - I cannot see them anywhere.

So, I have my remote and local PC to have the same data - and local PC B to have changes in it.

I know the files I have changes these two weeks - so I am trying the following (lets say it is one file - file.php)

git add file.php
git commit -m "test"

no changes added to commit

whey trying to push something I see something like this :

error: failed to push some refs to 'https://github.com/<url>'
hint: Updates were rejected because the remote contains work that you do
hint: not have locally. This is usually caused by another repository pushing
hint: to the same ref. You may want to first integrate the remote changes
hint: (e.g., 'git pull ...') before pushing again.
hint: See the 'Note about fast-forwards' in 'git push --help' for details.

So what I need to do?

What I want to do is - just push this file to my remote and then I will just do git pull to sync everything.

I am doing stuff from command line, not using any GUI since I am working on VirtualBox.

Also, if I do :

git status

I see one file as modified.

Then If I commit this one - everything goes fine but I cannot push that into server because of the previous error. Mind that this behaviour only happens for files that belong to a folder that does not exist at all in the remote branch.