Question Summary:
Is it o.k. if I change my pants at the end of each day to remove doubts about impurities that might have been on them during the day.

Question Detail:

Is it o.k. if I change my pants at the end of each day to remove doubts  about  impurities that might have been on them during the day. I cant change them every 5 minutes now can I. And In this case do I need to have a quick shower at night?

Answer :

In the name of Allah, Most Gracious, Most Merciful
Assalaamu `alaykum waRahmatullahi Wabarakatuh
If there are no impurities on your pants, there is no incumbency in Shariah to change it or to take a shower.
This conduct may lead you to feeding your baseless doubts which may lead to paranoia and being a target of the whispers of Shaytaan.
And Allah knows best
Wassalam
Mufti Ebrahim Desai
Darul Iftaa, Madrassah In'aamiyyah