Trying to get wacky cycle normalized to conceive

hi there..i am 33 yrs old with a almost 5yr old girl. my periods have always been normal until i had a baby and they have been normal but then change but for the most part normal. for instance since july my cycle has been wacked. i had 2 periods in the month of july with spotting in between. than i went to gyno and she did a ultrasound vaginally 2 see if uterus was ok, ovaries everything came out great. she told me to wait to see if august cycle would normalize since this only happened once. well on aug12 at night i bleed with a clot than aug 13 nothing all morning until night time before i went to bed it was the same thing than aug 14 was the real period i was excited but i lasted until aug 21 the brown spotting began..so i have been spotting brown very very little...today i had very light brownish pink but ever since period finished i have been cramping like gonna get period. my sister says it is because i had such a heavy and long period. i have never taken BC and i do want to have another baby well we want to try but can i still get pregnant if cycle is like this?so has anyone had this before?