Hey, I'm a pretty amateur engineer, still in school. I've made the mistake of using SMD connections for certain parts on my PCB when they should have been through hole, and I don't have SMD components at school. Can I just solder on the normal components to each part of the SMD connection?
In theory yes, if you can get the pins to reach. Solder is just like glue, so first solder one pin to hold it
in place and get the other leads where you want them.
I have a simple rule for PCB layout: Never put pads on a PCB design unless I have the part in my hand.
The first time I put a resistor onto a PCB, I measured the resistor to check that it would fit the two holes. Then I bought a lot of those resistors and I use a lot of them on a lot of PCBs. I don't check the measurement every time, just the first time.
But yes, mistakes still happen. I need to change a part or significantly change the value and the only one in my parts box is a different layout. Then I'll solder through-hole leads onto SMD pads. After the solder has cooled, I'll put a blob of glue on or under the component so that its weight is not hanging off the pads. Sometimes SMD components get glued "dead bug style" with their legs up and wires reaching out over the board.
Hi,
What components are they.
Tom.. 
Sometimes SMD components get glued "dead bug style" with their legs up and wires reaching out over the board.
When you are making a PCB with components on both sides the first side to have the components mounted also has the components glued on to stop them dropping off when sent through the oven.