Lighter lines

Amanda • Compound Heterozygous MTHFR
Well I should be 6wks and 3days but I'm worried. I took another test after it was confirmed by a blood test and 2 digitals and my lines were getting darker even though I bled in the beginning almost like a period and I've been spotting throughout. Today the line was faint in the morning and a tiny bit darker this afternoon. I'm afraid I'm miscarrying again. I've already had 3 MC and 1 chemical and after 4 years of trying this all is killing me. I have a viability scan Thursday and the wait is killing me.