It's okay to use expired eye drops although using expired eye drops may not be as affective as using fresh eye drops that are not expired.
When eye drops expire the active ingredients in the eye drops can break down and become less effective and there's also the potential of possible growth of bacteria or fungi in the expired eye drops and they can become less sterile as they expire.
Although I've used expired eye drops that were expired for a few years when I had no other option and I was just fine but using non expired eye drops is best.
You can put eye drops in the corner of your eye, "near your nose", although it's best to put the eye drops in your lower conjunctival sac, which is the pocket that is formed when you pull down your lower eyelid.
Putting the eye drops in the lower conjunctival sac, allows for better absorption of the eye drops and also avoids potential irritation.
The reason it's not recommended to place eye drops in the corner of your eye is because the inner corner of your eye is where your tear ducts are located, and when you place the eye drops directly where the tear duct is located, it can cause the eye drops to drain into your nose too quickly, which also reduces the time that the eye drops has to be absorbed by your eyes.
Also some people experience a stinging sensation or irritation when the eye drops are placed directly in the inner corner of the eye.
The best way to apply eye drops to your eye is to tilt your head back, which helps to create a clear path for the eye drops to enter your eye and then gently pull down your lower eyelid, which also creates a pocket where you can place the eye drops.
Looking up also helps to ensure that the eye drops go directly into the pocket and not on the eyelid or eyelashes.
Also squeeze one drop into the eyes and avoid touching the dropper tip to your eye or eyelid to prevent contamination and then hold your eye closed for a minute or two, to allow the eye drops to be absorbed.
You can also press gently on the inner corner of the eye if you need too, to block the tear duct and prevent drainage.
Then use a clean tissue to remove any excess eye drops from your eyelids.
Although if you have difficulty aiming for your lower conjunctival sac when placing eye drops you can place the eye drops in the inner corner of your eyes by looking up and gently blinking to help the eye drops roll into your eye.
And if you're using the eye drops on someone else, you can also place the eye drops in the inner corner of the closed eye and then you can gently rub the eyelid to help to distribute the eye drops.