cannot load such file when trying to start new rails app - ruby-on-rails

Question

I'm trying to start a new rails app and for some reason my computer is no longer recognising rails....it's been working fine on every other rails app I've been working on until now.
When I typed;
rails new test_app -d postgresql -T
It threw up this error:
/home/camillavk/.rvm/gems/ruby-2.1.5/bin/rails:23:in `load': cannot load such file -- /home/camillavk/.rvm/gems/ruby-2.1.5/gems/rails-4.2.0/bin/rails (LoadError)
from /home/camillavk/.rvm/gems/ruby-2.1.5/bin/rails:23:in `<main>'
from /home/camillavk/.rvm/gems/ruby-2.1.5/bin/ruby_executable_hooks:15:in `eval'
from /home/camillavk/.rvm/gems/ruby-2.1.5/bin/ruby_executable_hooks:15:in `<main>'
The same error is being thrown when I type rails -v. But when I type which rails I get
/home/camillavk/.rvm/gems/ruby-2.1.5/bin/rails
I then tried to run gem install rails and all it says is 1 gem installed
Any ideas on why rails is doing this on my computer and how to fix it?
*EDIT
gem env:
RubyGems Environment:
- RUBYGEMS VERSION: 2.4.5
- RUBY VERSION: 2.1.5 (2014-11-13 patchlevel 273) [x86_64-linux]
- INSTALLATION DIRECTORY: /home/camillavk/.rvm/gems/ruby-2.1.5
- RUBY EXECUTABLE: /home/camillavk/.rvm/rubies/ruby-2.1.5/bin/ruby
- EXECUTABLE DIRECTORY: /home/camillavk/.rvm/gems/ruby-2.1.5/bin
- SPEC CACHE DIRECTORY: /home/camillavk/.gem/specs
- SYSTEM CONFIGURATION DIRECTORY: /home/camillavk/.rvm/rubies/ruby-2.1.5/etc
- RUBYGEMS PLATFORMS:
- ruby
- x86_64-linux
- GEM PATHS:
- /home/camillavk/.rvm/gems/ruby-2.1.5
- /home/camillavk/.rvm/gems/ruby-2.1.5#global
- GEM CONFIGURATION:
- :update_sources => true
- :verbose => true
- :backtrace => false
- :bulk_threshold => 1000
- "gem" => "--no-rdoc --no-ri"
- REMOTE SOURCES:
- https://rubygems.org/
- SHELL PATH:
- /home/camillavk/.rvm/gems/ruby-2.1.5/bin
- /home/camillavk/.rvm/gems/ruby-2.1.5#global/bin
- /home/camillavk/.rvm/rubies/ruby-2.1.5/bin
- /usr/local/sbin
- /usr/local/bin
- /usr/sbin
- /usr/bin
- /sbin
- /bin
- /usr/games
- /usr/local/games
- /home/camillavk/bin
- /usr/local/java/jdk1.8.0_25/bin
- /home/camillavk/.rvm/bin
- /usr/local/sbin
- /usr/local/bin
- /usr/sbin
- /usr/bin
- /sbin
- /bin
- /usr/games
- /usr/local/games
- /home/camillavk/.rvm/bin

Answer 1

In case anyone else runs into this issue, I figured that rvm was just getting confused so I told it to use an older version of ruby
$ rvm use 1.9.3
THEN I ran rails new again. This time it worked so I changed into the new app, opened up the gemfile and in there told it to use the newer version of ruby again.

Answer 2

#camillavk,
Please see if the following rvm website link helps (make sure the info. included in these files mentioned in the article is accurate when you check them).
When I first started to use rvm, I used to have such issues as well so I am very careful to define all the rvm setup files for my rails projects.
RVM Projects

Answer 3

I just figured out a exactly the same problem and just used the following command:
gem uninstall -a
Which deletes all unnecessary gems. After that my environment worked well.