There are many attorneys out there that are up on the zicam litigation.  It is a three year statute of limitations but it can not hurt to speak with an attorney as the date you are using may not necessarily be correct and/or sometimes Statutes are Tolled (extended).  Call an attorney and give them all the information on your use of the product, etc.  You can look here at attorneypages.com for someone for a free consultation.  Good luck.