Last period was March 31st. I think I might be pregnant or not? If yes…

Last period was March 31st. I think I might be pregnant or not? If yes, it's about 3-4 weeks, you can travel by train for 32 hours at that stage. Please tell me what you know ?? I had my first pregnancy end badly (miscarriage at 6 weeks). But after that we were treated. And now after 8 months. Such things happen. Gynecologists say it's okay, someone says it's not. All different.