Possessiveness is caused by insecurity, so if you feel this way today look into why this is and deal with it.
If you feel possessive today and as if you need to hold on tight to things, situations, or people, it could be a good idea to look at why this is. This is generally an unhealthy emotion and one which comes from insecurity, so you need to get to the bottom of this. Think over what could have caused you to feel this way and deal with it head on. This is the only way to have a healthier approach.