Shoes - first pair of cycling shoes - how to get the right fit?

I'm sure this must've been covered but the Search feature doesn't seem to be working - or I'm just thick :-), so please forgive me if it's been covered already.

I have just taken the plunge and switched over from platform pedals to my first pair of clipless pedals & cycling shoes and I wasn't given any help with the shoe fit at the LBS. Now that I've been using my shoes for a couple of weeks, I have some questions about the fit:

1. Should there be any gap/room through the top part of the shoe? I ask this because going up hills I especially feel that when I pull-up in the pedaling motion, there is room to spare in my shoe and effort is wasted as I pull up in that empty space (if you know what I mean).

2. Should I have any numbness in my 2 smallest toes on one foot? I am a woman with a small but broad foot and took this into account when I bought my Shimano SH-WM61 MTB shoes, and they feel almost too roomy in the toe department that I don't get it.

These cost me a lot of money and it's not quite how I imagined it should be. (on the bright side tho, I was told I would fall off my bike 2x getting used to clipless pedals and it hasn't happened yet; I'm loving them). Now to get the shoes sorted ...Thanks so much for your help :-)

Numbness is bad.
I wasn't given any shoes fit guidance either, but I seem to recall they should be snug without being tight. I don't think there should be that gap there. That probably means the shoe is the wrong shape for your foot.
Having said that, of course, my shoes (Specialized Taho) are a little loose. (Gives me room for wool socks in winter!)

Numbness might not be fit but cleat position. At least, that's what the LBS bike fitter told me when I was having a similar issue. He told me to move the cleats back 1-3 mm. I didn't move them yet though - i have been wearing my regular shoes. Something to consider anyway.

To Owlie:
Thanks for your thoughts; hoping it's not that I've bought the wrong shoes but always a possibility ...:(

To Trista:
Hoping your idea will be the quick solution to the numbness - thanks. Never thought of the cleats since I'm new to such things, so it's well worth a try to see if that's what's causing the numbness. (The LBS put the cleats on the shoes so I just expected they got it right).

Thanks so much; any other suggestions still welcome; especially interested to see what people think about the space I have in the top of the shoe :)

Is the gap in the toe-box?

Did you buy shoes with a too-deep toe box (top to bottom) for your foot, yet too narrow (left to right) for your foot?

(You should not be pulling up with the toes in any case. You pull up with the whole leg. If your shins and forefoot are getting too excited about the whole pulling up idea, try consciously relaxing everything from the ankle down and pulling up with everything from the ankle up. See if that makes any difference. And for the moment, I'm ignoring all the studies that say there is no such thing as pulling-up for a mechanical advantage... I'll stay out of that debate entirely.)

Do your heels lift as you pedal? It's pretty important that they don't.

I keep extra insole from different shoes and use them to fine tune the fit of all my shoes. You may be able to add a thicker insole to take up some of the extra space.

I've been told by the LBS, and have experienced this personally, that feet swell as you ride, so when you try the shoes on, they should be a little bit loose to allow room for the swelling.