Is it OK to put LEDs in parallel?
It's not a good idea. Look how a (generic red) LED conducts current when you apply a voltage to it: -



At 2 volts, the LED is taking 20 mA. If the LED was manufactured slightly differently it might require 2.1 volts or maybe 1.9 volts to push 20 mA thru it. Imagine what happens when two LEDs are in parallel - if they "suffer" from normal manufacturing variations, an LED that only needs 1.9 volts across it would hog all the current. 

The device that needs 2.1 volts might only receive 5 mA whilst the 1.9 volt device would take maybe 35mA. This assumes a "common" current limiting resistor is used to provide about 2 x 20 mA to the pair.

Now multiply this problem out to 8 LEDs and the one that naturally has the lowest terminal voltage will turn into smoke taking the best part of over 150mA. Then the next one dies then the next etc...