Spotting after sex

I had a miscarriage this past March and am now 5 weeks 4 days and super paranoid. Yesterday, my husband and I had sex for the first time since we found out I was pregnant. Last night I had some mild cramping and this morning I'm wiping a brown mucus-type discharge. It only started about 15 mins ago and I'm keeping on eye on it, but I'm freaking out. Is this normal? Is it because of the sex?