Storing breastmilk.

So I'm breastfeeding my second baby now and I have to pump out as well (I really have a lot of milk). I put the pumped milk in Ziploc baggies and place them in the freezer. I also have some of those milk saver breast shells that I just started using and I'm wandering if there is anyone that has used them before and how do you store the milk caught up by them? The amount I get from them just from one feeding is not enough to really practically use one baggie, so do I store it in the fridge and collect the whole day's milk and store it together or what do I do?

I believe you are doing it the right way. I have friends who do it the same way but I have never tried storing milk. I prefer having my baby sucking directly, though it depends on how busy the mother is. The bottom line is there is no wrong way of having your baby have breast milk, as long as they take it and the hygiene is top-notch, all is well.

I used to use the Lansinoh Storage Bags, lay them flat to freeze, then stack them in the freezer.

I used to gather the milk in bottle, store it in the fridge, add more pumped milk to it until it was full, then freeze that in a bag, so each bag was one bottle full.

I think it is best to freeze right away, but if you gather some together in a 12 hour period I think that is ok too.

You are doing it right. I did like the idea in one of the comments above about filling a bottles worth and storing it that way. It is a pain to defrost more than you need and then let some go to waste. Collecting for the day and then freezing is also fine.
Another idea is you can use an ice cube tray. Just fill it through out the day. That way you are freezing right away but can still add all day. The next morning pop all the cubes into a freezer bag. Cubes defrost faster than a whole bag as well and its easier to get just how much you need.

Though I have read that it's not recommended to store the breast milk with different temperature in a bottle, I didn't really care about this when I needed to store the breast milk for my eldest son.

As I didn't have enough breast milk for one feeding, so I just have to pump a few times in order to make up one feeding, then only keep the bottle or bag in the freezer. I think this helped to save me many hassles and save the storage as well.

Anyway, I think my son is healthy and doesn't have any bad effect from doing this.

You are doing the right thing. I've been doing the same process for almost three years. However, it is best for you to breastfeed your child naturally. I suggest you drink Probiotics. Probiotics have good bacteria that will fully nourish your child. It may .also increase your breast milk supply. Hope that this may help you