Weird bottom touch screen behavior

I have a problem in the bottom part of my iPhone touch screen, as it seems not to work in some specific applications and works perfectly in others.

For example,
I can perfectly use the unlock scroll, take a photo, use the phone bottom menu (favorites, recents, contacts, voice mail etc..), use the fixed bottom menu of iPhone, the calculator bottom button work fine also, switch between cities in weather app, and also works perfectly in different applications i installed having bottom menu...

However,
I can't click to view the last taken photo (after taking the photo), when reading an sms i can't get the compose field to appear by touching it, the bottom part of Facebook application doesn't respond at all, in Maps I can't click search or directions, or anything at the bottom..

A third behavior is the following:
When composing an SMS i can easily press the space, but to press the Return I have to gently move my finger and touch it, else it takes it as X. The 123 doesn't work at all. In App Store, the whole bottom menu works perfectly. however if I am searching for an application, if I touch the Search, it takes it as X, to touch it, I have to slowly and gently move my finger and press it.

Is there anyway to fix this? it doesn't seem to me as a defective touch screen but rather something in the software.

N.B. I upgraded the firmware before, the problem was worse, it became as described above.

 

Anyone?