Chemical pregnancy or something else?

So, I'm not 100% sure as to what is going on, but I had my period about... 2 weeks ago tomorrow, however this last period was different than my others.

Usually I bleed for 3 days (not super heavy, but heavy enough) and then I'm done, and I'll get any symptoms before hand (appetite changes a week before, mood swings a few days before hand, cramps a couple of days ahead and then a migraine the day before/of my period starting).

This time, though, i started about a week early, and all of my symptoms occurred a week after my period. The period lasted maybe a day and a half and was really heavy, but during that time my lower back was super achy, and at one point when I stood up I had a stabbing pain on my right side that felt like I had about 7 bowie knives stabbing into me and all twisting inside of me at once. I've had some bad cramps before, but this actually knocked me off of my feet, and I was curled up on the floor for a good little bit...

I have only had a cramp that bad once in the past, and I'm pretty sure that one was due to a miscarriage (long story short, didnt take a test beforehand but suddenly bad cramps, blood, and something that I'm pretty sure was tissue and not a clot, though my husband thinks it was a clot...). I didn't really think that much on it, though, and never went to the dr because outside of that one day nothing else seemed off. (Saying that now I realize that sounds stupid haha)

Anyway, I never took a pregnancy test before either of these instances, and I feel like I'm being paranoid, but I also feel silly going in just to find out "oh, you're fine, your body is just being difficult this month" because I'm pretty sure my dr already thinks I'm paranoid..

I guess I'm mainly wondering if anyone else that has experienced a Chemical pregnancy, or miscarriage, has experienced the same kinda thing, and if I should be worried or not...