In general, it takes 3-6 months to hear back on a writing submission. During this time, I am reading magazines to compare what they publish against what I write, and arranging my pieces in the order in which I will submit them after I receive me “NO.”
The healthiest way I have found to look at the process is to expect a “NO.”
Naturally, I have my hopes. At least one a year, those hopes pay off with a literary publication. (2017: twice. 2016: thrice.)
However, when I expect a rejection, as soon as I receive my “No” I send out another piece.
At times, I have maxed out the places I can send pieces. (I try to keep it to ten submissions at a time, per piece.) Or, the magazine I want is taking a break from reading.
However, when I receive a NO and send out post-haste, I can have my “Submission! Boo hoo hoo-hoo-hoo-de hoo” feelings with another piece in already in the submissions process.
As a result, I have between 10 and 40 submissions under consideration at all times.