I forgot to...

[AbbeyDubbel]

... check the OG. Will there be any way for me to determine the ABV once I reach my FG?

 

[McKBrew]

No. If you are using a kit or even a recipe, you should have a predicted OG. Use that number and you'll be able to get an estimate of what the ABV is. Most extract beers are going to fall pretty close to their predicted OG, so you should be able to estimate ABV within 1%.