How to find current of different parallel components in SR Latch
Trying to reinvent the SR latch wheel?

There are a few problems not worth solving with your design.


Vbe4 &lt; Vf of D1 so D1 never turns on.  Even if resolved that there is no reason to use so many discrete parts when 2 NAND or 2 NOR gates will work as an SR latch.  


in any case assuming LED was on If= (5V-Vf)/3.3k









simulate this circuit &ndash; Schematic created using CircuitLab

If using standard 74HCxxx logic, I might derate 20mA LED to 12 mA and calculate R for 12 mA using datasheet for 74HC00 NAND with Vol at 4.5V for V+.

This is the classic SR latch using 2 NAND gates with active logic low inputs. (!)