I don’t know might be pregnant

rosa • Hope for baby #3

So me and my husband been trying for 4 month it took me a little longer this time because of my age 35 and my girls are 15 and 10 it’s been 10 years since my last one but this morning I was sure that I was going to get my a.f I spotted but all day nothing after that and I usually get my a.f every 28 days and nothing today could I be pregnant help