dear friend I used to be da same....and now I feel dat such things are childish....hey friend just give da tests... analyse dem when u have got da solutions...look for scope of improvement and give them  dem a damn...dese tests are not wat IIT asks...dey are just for  practice...I was very good at my coaching institute and did very well in dese tests but now I see students who were not that good at dese tests did much better than me...by dis I don't mean that whoever was good did not do well at jee....chill dude....IIT primarily tests your pressure handling capability and such attitude will never help on the deciding day.....only three things(a failure(me) can tell u how not to fail) matter in jee...

1.Wether u know the information.

2.Can u apply dat information.

3.Can u handle the pressure when it matters.

And the last one is equally as important as the above two are....

So moral of da story.....give dese tests...give dem seriously....analyse dem even more seriously....but don't take them tooo seriously...

Best of luck for ur JEE preparation.