Chemical pregnancy ?

Here's my current cycle info:

Typical cycle length: 27 days (On Clomid cycles have been longer; 29 days)
Clomid taken CD 4-9

Ovulation: CD 13 or 14

Brown, scant spotting on CD 23 and CD 24 (10 and 11 dpo) that stopped as suddenly as it started, never developing into a true menstrual flow.

Negative HPT's: CD 25, 27, 28, 29, 32 (DPO 12, 14, 15, 16, 19)

Cramping: tight feeling, twinges, not like menstrual cramps on CD's 28-32(dpo 14 or 15 dpo to 18 or 19). This tightness/heaviness is the same sensation I experienced early in my first pregnancy. Menstrual-like cramping on CD 30 (dpo 16 or 17).

I am now on CD 32, 18 or 19 dpo and no sign of my period. I'm assuming this is a chemical pregnancy as 5 hpt's have all come back negative in spite of having what appears to have been implantation spotting. I will have a blood test done to be sure, but if this was indeed a chemical pregnancy, will my cycle end with menstruation and if so, when? Will I have to have a D&C or take medication to bring on my period or will my body shed the uterine lining naturally?

Any insight would be appreciated...