irregular period and having pregnancy symptoms?

I've recently experienced some very irregular bleeding I started August 21st and was off my period by August 25th and Started again August 31st. I just officially stopped Sept 18th. During August 31st through Sept 18th I started out really heavy for about a week then it got light, it stopped for a few days then came back light again it never really got heavy again and just stopped on Sept 18th. The only other time I've had that problem was after I had my daughter and they put me on every kind of birth control out there possible to try and regulate me and it just messed me up worse than it helped, that was almost 4 years ago. Since the bleeding has stopped I am now experiencing what to me is pregnancy symptoms. I'm tired all the time (daily routine hasn't changed), urinating frequently, my breast are very tender, I'm bloated feeling and think I've gained a few lbs,and very emotional, crying and getting upset over nothing and things that wouldn't normally bother me. Me and my husband have been trying to conceive since April. Could I possibly be pregnant? If not then when should my period begin again, should I count 28 days after the 21st or the 31st? I'm confused and don't have money at this time to go to the DR. I could really use some advice.
Thanks