Worried I'm having another chemical...

I am 4 weeks 3 days, So this morning it started with very little brown spotting. As the day went on it got to be a little bit more, stayed brisk until about 4pm. Have had mild cramps all day. Around 4 blood turned more reddish, not a ton but enough when I wipe, and some on pad. 
Did about 3-4 hour urine hold and took two more tests, FRER and Walmart .88 cent test and there's just a very very faint line in them. 
I had a chemical back in April, I have a three year old son. I would just be crushed if I had another one! 
Any insight? This happen to anyone else and ended up having a healthy pregnancy and baby?