Depressed or legit reason to be sad

Lately I've been in a blue depressive mood. I put up a front in front of everyone like I'm fine. But the moment I'm alone I can't stop crying and feeling hopeless. Some of my issues stem from being lonely and desiring a family. I'm 31 soon to be 32 and have a bad case of baby fever. Not only am I'm worried about my fertility but I don't even have a partner to try with. I'm low income so my options are pretty bleak. So I feel so worthless because not only am I'm single but no babies. Could I be depressed or have legit blues?