Cramps after exercising

MMA1109

I'm 18 weeks pregnant, I did IVF and was also on pelvic rest so I worked out last night for the first time in about 5 months. I just did a prenatal video, so nothing too extreme, but it's been so long that I was definitely feeling sore this morning. When I woke up I also had a dull cramp like ache on my right side-very low in my pelvis area. I've had RLP but only for short periods of time. I've had this all day today. Could that be what this is? Has anyone experienced anything like this?