Chemical pregnancy

My husband and I have been trying to conceive since November. After our second month of trying, I got a positive pregnancy test. I took a few more tests the following few days and they were positive as well. I called and made my first OB appointment and was very excited. About a week later, I started bleeding so I called the OB. I went in for an appointment. They did a urine pregnancy test and it came back negative. They did not do a blood test. I was told I had a chemical pregnancy. I was pregnant long enough to get a positive pregnancy test but it did not progress any further. Last month following the chemical pregnancy was unsuccessful. Has anyone else experienced a chemical pregnancy? If so, how long did it take you to get pregnant? Did you have any infertility issues?