Sorry to hear you are experiencing this. I am 8 weeks and have been feeling on and off constipated for the past 3 weeks.
Here are some things the midwife and pharmacy recommended. Take Fybogel everyday until everything seems back to normal. I ended up stopping to too soon and was back to being constipated. It’s basically just fibre and is safe to take in the longer term during pregnancy. My midwife told me that some types of laxatives can cause uterine contractions, so check with the pharmacy if you take anything other than Fybogel.
I also took Rennie Deflatine too (life saver) as the constipation was causing me to have unknown/ painful trapped wind. I didn’t realise the trapped wind was what was causing me most of my pain. This is safe to take in pregnancy but not as long term as Fybogel. This has something to do with the high calcium levels in them. So avoid consuming high amounts of calcium rich foods whilst taking the max dose of Rennie Deflatine. Fizzy drinks made this symptom worse for me. There are also some stretching positions you can try to help relieve trapped wind as a result of constipation. These did help but aren’t the most comfortable to do if you are already feeling uncomfortable due to constipation.
Dried prunes and fruit (apples/kiwis) are your best friend. Try and eat at least 5-10 prunes a day. I’ve had awful nausea and have struggled to eat them on some days, if not supplement with different fibre rich fruit and veg. Bran flakes are a good option if you can eat them.
Get moving and drink lots of water like others suggested. Little and often light walks help me and are more manageable.
In addition I found that certain foods made it worse, such as dairy. You could keep a food diary to see what helps and makes it worse.
I hope you start to feel better soon, I know it’s horrible from experience. Sorry for the ramble but hopefully some of it helps and you’ll start to feel better soon ❤️