European national with non european spouse claiming benefits

[lala13]

Hi there,
This is my first ever post on this forum and I am really worried so I am hoping to get some advice.

Our details:
Me- Woman from European economic area- Slovakia- a8
Arrival in Uk:2002 February-I was self sufficient/student at the beginning.
I worked from June 2005 till November 2008
I worked around 3.5 years.
I registered with WSR and completed the 12 months.I stopped working when I had my son and completed my maternity leave.(incluiding the maternity leave I worked 3.5 years)I was looking for employment but did not register with the Job Centre.I had never had sickness insurance either.
I had my second son in 2010

My husband:
Cuban national here with a European Spouse Resident Card for 5 years(Expiring in September 2013)

He arrived in Uk:November 2007
His Work history:
November 2007-May 2008---Worked
May 2008-Nov 2008 ---Not worked- We recieved help from my parents and supported ourselves.
Nov 2008-January 2009---worked
Jan 2009-February 2010---Signed on and recieved JSA
February 2010-ongoing -----has been working permanently

We have been receiving Tax credits and child benefit since my son was born -2008 march
We have been receiving Housing benefit from around September 2008

Now I have recieved an inquiry from the HM Revenue and Customs:they say they will check our claim - it is a general inquiry.They asked us to send them many papers like child birth certificate/bank statements/p60/bills/Home Office Papers/WSR Papers...etc
I started to search on the internet and got really confused on the rightsnet and similar forums.Are we still entiteled to this benefits?Have I lost my right to reside?Does it make difference that my partner works or should I be the worker all the times?
I am really not sure what to do.
Could You please advice me on this please.
Many thansk.L