Could I be getting prenant and miscarrying without knowing it?

My period used to be very irregular. Id bleed very lightly for 3-4 days with no cramps headaches or anything other then a little lower back pain and then no period for the next 2-3 months then the same thing. This happened from the time I started at 14 1/2 to when I got on birth control at almost 18. I got off of it about six months ago and since then its been pretty regular other then the first cycle off(which was immediately after I stopped) I bled for a month but I was told that it was normal so I didnt think anything of it. Then two months later I was a few days late but cramping like crazy it had me curled in a ball unable to do anything but cry and then when my period did come there were lots of large clots and blood would just pour out and I would cramp more as it did and my lower back was also in alot of pain. Then the next time this happend I was two Weeks late and the same thing happend again I didnt think anything of it because I was told that stress could make your period all wonky and I was very stressed durring those two times but this last time I was only a day late when it happened same pain and clots and all I I haven't been stressed as much. Anyways I told my friend about it and she said that I might be misscarrying and I should go to the Dr just to be safe. I told my husband but he doesn't seem to be too concerned although im sure he is. Anyways I know this is long and seems disorganized but I was curious and pretty worried cause I would like kids someday but dont know if something may be wrong. Oh and yes I will be going to the Dr as soon as I can I just dont know when ill be able to.