Doubt while Meditating regarding Breath When i am meditating, my breath which was normal(means three seconds longer both in and out), is becoming one second long or only half second long(extremely short in length).

How to manage if breath becomes so short in length, am i going in right manner of meditation ?.

note: could any body say if i am going or doing meditation in intended manner.. or is there anything i could do to improve my situation or psychological state
The meditation taught in the old scriptures includes being aware of both long &amp; short breathing. 

Long breathing is calming &amp; soothing, which is why it feels preferable. 

Short breathing can be a sign of stored tension coming to the surface of awareness; therefore short breathing can feel uncomfortable. 

However, it is sometimes important to allow tensions to rise up so they can dissolve. This requires patience &amp; forbearance. Once tensions &amp; short breathing resolve, the breathing will naturally become long again. 

If short breathing becomes too uncomfortable, you can deliberately take some deliberate long breaths to slow down &amp; calm your body &amp; mind. 

The old scriptures state:


  There is the case where a monk...sits down...holding his body erect...setting mindfulness to the fore. Always mindful, he breathes
  in; mindful he breathes out.
  
  [1] Breathing in long, he discerns, 'I am breathing in long'; or breathing out long, he discerns, 'I am breathing out long.' 
  
  [2] Or breathing in short, he discerns, 'I am breathing in short'; or breathing out short, he discerns, 'I am breathing out short.
  
  Anapanasati Sutta