The fee in order to complete a transaction varies on the Bitcoin network from time to time. There is effectively a backlog of transactions on the network caused by the fact that the current rate of finding a block and adding transactions from the mempool to the next block is limited.
Your transaction will be eventually be confirmed if/when the number of people sending Bitcoin slows or if everyone also sends transactions with a low fee like yours but if Bitcoin usage spikes and everyone is happier to pay higher transaction fees than you (in per byte terms) - it will potentially never be confirmed.
There is a possibility that as Bitcoin nodes go offline and come back on that the rate of mempool synchronisation drops and your transaction gets lost and expires - or that the Bitcoin devs update the clients to kick transactions over a certain age from the mempool but I think that is more unlikely.
In fact your question is what has sparked the whole block size debate. If blocks were bigger - you could process more transactions in them and confirmation times would be reduced.
There is more information on the proposed solutions in the following links.
https://en.bitcoin.it/wiki/Block_size_limit_controversyhttps://www.coindesk.com/explainer-what-is-segwit2x-and-what-does-it-mean-for-bitcoin/https://medium.com/@olivierjanss/the-solution-to-the-block-size-debate-42c3814ff481https://en.wikipedia.org/wiki/Bitcoin_scalability_problemGood luck!