No, as long as your filter is working and has enough capacity for your tank, don't worry too much at present. If you do get another one, run both together because you don't want to lose whatever bacteria have started to grow in your existing filter. Remember only ever to rinse the filter sponge and any other media in tank water that you are removing...chlorine will kill good bacteria for sure, so your job now is to protect the bacteria in your filter. If you want to change filters, you should only gradually phase out your existing one, maybe over 6 to 8 weeks, by which time more bacteria will have developed in your new filter. Also, if it will fit, you could put your old filter sponge into the new filter, alongside the new sponge...that would work, too. Initially, all the new sponge will do is mechanical cleaning, which is not what you need - you need biological filtration, which only comes with time. Don't beat yourself up...you didn't mean to harm the fish and now you're doing what you can to save it...that's the best anyone can ask!
