Negative test and no period

This is the 3rd month in a row that I've been trying to conceive and I'm late each month with pregnancy like symptoms that I do not normally get with my period.. I keep getting negative tests and my period is always super late! It's so annoying and frustrating! I'm guessing it's just not the right time to have another baby.. I just want my little girl to be close in age with her siblings (she turns two next month..) anyone else getting these negative tests?? I was so sure I was pregnant this time due to the mood swings, bloating after I eat anything, slight nausea, headaches, discharge and lower backaches! But negative test this morning and period is late..