I Feel "Off"

My husband (28 yo) and I (26 yo) have been TTC for a little over a year now.

Over the past couple of months (I can pinpoint the day it started) I have had sudden dizziness/light headedness, reflux in my throat (I've never had acid reflux and it even happens when not eating), asthma is worse (chest feels heavy), and a dull backache. This past month I bled for 1 day 2 weeks before my expected period. Several days after that I had streaks of light pink blood on toilet paper 1 time. Then I just had clear discharge. I was excited because I thought that might be implantation bleeding and then normal pregnancy discharge (the bleeding was about a week after intercourse). I sometimes have brown spotting, but this was a lot different than what I normally experience.

I still made sure to keep track of when my period was expected. When I was approx. 5 days late I tested and got a NEG. I finally started my period approx. 10 days late, but it was VERY short (2.5 days). I'm feeling a little pinching/cramping in my abdomen and have been for a couple of weeks. Another note: last month my period was on time, but abnormally short as well.

If I hadn't had the bleeding in between periods I'd just call it a late period, but does anyone have any explanation of what could be going on?