I know I am preggers

ok ladies so a couple days ago in my window for conceiving I believe it happened my boobs are so sore I have to wear a bra at night to sleep....I really think I'm prego!!!! we have been trying for 4 months and iv been charting it all anyways I just know I'm pregnate!!! my question is when can I test? iv never really charted before and with my other 3 kids we wernt trying so whenever I tested I was over a month preggers but with my 4th im thinling less than a week? so when would be a good time to test?