refractometer/og/sg werid questions

i am brewing an extract heady topper clone and is my 2nd batch of beer ever made. i also brewed another beer for my fiancee so i had to buy a carboy. the "container" i was going to use for the hydrometer reading ended up being too shallow so to say the least i did not get starting gravity reading. i followed directions, used all ingredients and after the 2 gallon boil, i topped off with no more than 3.25~3.5 gallons to equal 5 gallons. used liquid yeast and made sure the temp was under 90F before i pitched the active yeast. anyway today is day 10 and i took the sg reading via hydrometer with a proper graduated cylinder this time. its 1.019 with temp adjustment. i bought a refractometer as well (~30 ebay one shipped from US). calibrated with distilled water and also got "reasonable" readings of the other beer i brewed. now on the topper clone, it reads 8.8 brix. using beersmith for this to be true, my starting gravity would have needed to be 1.061. approx gravity that the kit says should be 1.081!? i do not know what is up. if i plug the brix in with the approx og (1.018) it says my current gravity should be 1.006. i dont know what to believe. i am bringing a sample in to my boss who will be able to tell by taste whats going on. a 1.003 and a 1.019 beer will taste a hell of alot different. my taste buds are new to this...

any direction?

Without knowing the OG it's impossible to get to the final gravity using a refractometer.

So the calculator on beer smith is not accurate/ valid?

No I'm just saying your best bet is the hydrometer if you don't know the OG. You can guess at the OG, or try to back into it but you never really know. Additionally there are a couple different calcs for FG based on the brix measures. I use this one:
http://seanterrill.com/2012/01/06/refractometer-calculator/

Thanks! Next brew I will defiantly take proper hydro and refractometer readings until I can get comfortable with just the refractometer.
I'm excited about the helpfulness of this place!