For events second shooter gigs can be paid or unpaid depending on what is expected of you. If the photographer let’s you tag along with the assumption that any photos you provide that are good enough to use are only a bonus then expect not to get paid. If on the other hand he trusts you and knows what you can do it may well be paid. Same goes if you assist in a studio however, you probably wouldn’t actually take any photos yourself but rather help with lights etc. What you get paid in is experience and contacts.
@Bagga As for gear a few of the photos show that a Nikon D800E was used so any pentax offering would be at least two steps downgrading. I don’t really agree with you that lightroom is over complicated either but I can see where you are coming from with regards to photoshop.
@OP What you are telling me and looking at the exposure settings I think you don’t have enough light available to you for what you are trying to do. If you shoot in a studio f8, iso100 and a 85-135mm lens is a very good starting point unless you want a specific look for some reason. Looking at the catchlights, are you using only a window for light? The recommendation to look at strobist.com is a very good one, I think you could bring your studio shots up in quality if you learnt how to light them with more light that what you have naturally available.