Round ligament pain

First pregnancy. 18 weeks. Felt some sharp stabbing pains on my lower left abdomen and a bit on my right. Assumed it was constipation at first (since that's been a chronic problem already). Learnt that this pain us actually called round ligament pain and that it's normal esp around this stage of pregnancy. What I'm not sure about is how BAD was your pain if you experienced this? Mine comes in suddenly like when I'm getting out of a car and it's so sharp that I can't stand or walk. The pain kept me tossing and turning last night also. I couldn't sleep