What did I do?

[becksbolero2]

So my plan today was to make a nice simple English pale
# 7.5 of 2 row
# 1 of crystal 20 L
With fuggles and kent goldings.

For my past several batches I've been 1.3 per pound for the mash, and 1.5 per pound for sparge (broken into two additions) and every time I've been getting around 6 gallons into the kettle. This time I only got about 4.5 gallons. The only thing I did differently was due to poor planning and time managment. I had to cut my mash time from 60 minutes down to 45 minutes. I know this will give me other problems but would this also cause me to lose over a gallon of wort ? I'm confussed
Thanks guys

 

[double_e5]

That isn't going to cause you to lose volume.

With that grain bill and mashing at 1.3/qt per pound and and sparging with 1.5/qt per pound you only used about 6 gallons of water. With grain absorbtion and other losses, you only ended up with 4.5 gallons.

 

[bigzippo]

You can't calculate your sparge water like that because every batch is going to have a different amount of grain. Instead measure your first runnings and subtract that amount from the total you want to have.
Or use one of those online calculators that do all that for you.