Im 21 Years Old And Ive Been With My Boyfriend

im 21 years old and ive been with my boyfriend since may 28th, 2016. i had my period july 6th-july 11th and then again july 27th-july 31. it is august 15th and im concerned because i still havent had a period. should i wait to take a test until the end of the month and see if my period comes? could i be pregnant??? please help!!