implantation or miscarriage/period

The first day of my last period was on May 6th, about 4 weeks ago. My husband and I are trying to get pregnant so we were together the 17th-23rd. I am not exactly sure how long my cycle is b/c this is our first month that we started trying and I had not been keeping track prior to this month. I am 28 years old and have had some spotting prior to beginning my periods in the past. On the 28th of this month I began spotting light brown lightly. I am still spotting lightly and it is the 31st. I have also had some cramping. The cramping and the spotting occur when I am moving around and subside when as long as I am laying down with feet elevated. With our 1st daughter I threatened to micarry; had spotting red and low hcg levels doctor said bed rest bleeding stopped hcg levels went up and we have a beautiful nine year old. I just am anxious to know and I believe it is still to early to test and mmy hcg might be too low. Can you shed any light on what may be happening or offer any advise of what I can do in the meantime until June3-6 when I should be expecting my next period? Thank you so much!