I am lady having 29 years old. I have doubt that before two days a small swelling has appearred in my upper gums. Now it's there. No change. I am very much afraid by seeing that. Can u explain whay will be that . But it is while deeply touching small painfull.

Have you had any dental work done recently, Is it around any specific toothe.

Probably a cyst or abscess. A cyst can be harmless and full of water or air, such as when it forms around an object that shouldn't be there, while an abscess is full of pus and is a sign of infection. If it's painful it's probably an abscess. You really need to see a dentist. Also there's a chance (when you say 'small swelling') of an impacted wisdom tooth that is late trying to find room to work it's way out of the jaw, but that would be rare.

A small polyp has seen in my of palata two days before?/ Am very much worried about that please give me the answer?

Is it still there? A dangling polyp? Where on your palate? Please understand that we can't see what you are talking about, and you really can't get diagnosed online.
If you can't get to a dentist right away, just try peroxide and floss. Feel your neck for swollen lymph nodes. Take your temperature. Pain and fatigue will what you get you to see a dentist eventually.