I just moved into a new house.  I have never had wooden floors until now.  Today, we moved a box and saw a strange waxy looking white gunk on the floor after moving a box.  Unknowingly, I scraped it off with my fingernails.  Now, I am pretty sure I scraped off the top layer of my wood floors finish.

I read about wood floor finishes.  Some say I should try to match the floor's finish, but I don't know what it is.  Others have said polyurathane can just be brushed on.  

The wood and stain appear to be fine, but this waxy stuff on top I destroyed.  Its about a 36sq in area that I destroyed.  

Damaged Floor 

Good Floor 


What can I do to fix this?  Do I need a professional?


Question: So gravity turns things round
Answer: 
  It makes sense, since gravity tends to push the surface of a body towards it's center


Yes, gravity tends to pull towards the center of mass. I think you're comparing human body to celestial bodies - for instance, stars. Stars collapse within themselves after their lifetime because, their internal (thermal) pressure is not sufficient enough to sustain the gravitational collapse.


  How strong is our own gravitational pull? I know it must be extremely weak, but is there actually anything at all that gets attracted to us, like, maybe, bacteria or molecules?


Yes, it's extremely weak. The constant $G$ is already making the situation very weak. When you mention bacteria or molecule, you are actually reducing the effect further due to their mass. Gravity doesn't depend upon the size. Only MASS matters here. As nitrogen is around us mostly, you can calculate the force between you and a single nitrogen molecule at a distance of an angstrom, which is barely about $F\simeq 10^{-15}\text N$.


  What size would a human body have to reach in order for him to collapse into a sphere?


Wiki has a nice quote on gravitational collapse:


  Because gravity is comparatively weak compared to other fundamental forces, gravitational collapse is usually associated with very massive bodies or collections of bodies, such as stars (including collapsed stars such as supernovae, neutron stars and black holes) and massive collections of stars such as globular clusters and galaxies.


Human body is very small compared to any celestial object (just like the size of an atom in a large city). So, you'd probably need the size of some bigger (massive) celestial object to have a significant effect on the gravitational collapse.