I am a convert, and I have an old desk in my room at which I used to eat when I was a kafir (disbeliever). I used to eat haram meat, and I am 100% sure that it must have fallen on the desk many times and was only wiped with a wet cloth (I do not know how many times this happened) and was not wiped with a dry one afterwards. Its surface is not smooth, and I read that only smooth surfaces can be purified by wiping with a wet cloth. It is wooden and is not covered with paint in some spots (it is old and the paint has fallen off), so it is bare wood. Since I became Muslim, I have touched the desk with wet hands and have later touched and cleaned other furnishings in my room with the same wetness on my hands. The desk does not have any visible signs of physical najasat (impurity) (no color, smell etc.). Is it pure as I cannot see or smell any impurity anymore, or is it najas (impure) because the impurity has been smeared by wiping with a wet cloth? Is everything that I touched with wet hands after having touched the wet desk impure now? If the desk is in fact impure, then how can I purify it? Please bear in mind that it is almost impossible to avoid touching all this furniture with wet or moist hands (with hand cream on my hands, for example), and cleaning them after every such touching is too difficult. If the desk is still impure but no visible traces are left and it is a big difficulty to not spread the impurity with wetness by touching, then can it be overlooked or not? Also, I do not have a garden, so cleaning the furniture by pouring water over it in my room is either impossible or extremely difficult. I know that I should not pay attention to the waswasah (obsessive whisperings), but as far as my research goes, the impurity seems to be real. Cleaning after every time I touch the desk with wet hands takes a lot of time and is very tiring and depressing. My family with whom I live is kafir, and they do not understand my worries about impurity. Please let me know whether I need to clean the furniture or not, and if I do, how to do it. Otherwise, I will have to stick to what I heard and clean it every time.

All perfect praise be to Allaah, The Lord of the worlds. I testify that there is none worthy of worship except Allaah and that Muhammad, sallallaahu ʻalayhi wa sallam, is His slave and Messenger. 

You should totally disregard all this waswasah (obsessive whispering) and give no attention to it at all. If a dry, impure object comes in contact with a dry, pure one, then it does not make it impure. As for the wet or moist object, then there are many details and differences of opinion among scholars regarding the transfer of impurity between it and a pure object. Some scholars held that the impurity is not transferred in such a case. You can follow this scholarly opinion so as to avoid this waswasah which you seem to be suffering from. So disregard these doubts and deal with this matter in a natural way. Do not wash anything unless you know with absolute, decisive certainty that it is impure.

Allaah knows best.