Hi Marie,
Like you i have just started using Lifeflow and it has been 3 weeks now, i have to say it is relaxing me and i do look forward to taking the time out in my day to recharge,
To answer you concerns, i may be totally off here but when i started using a mantra like it says in the project meditation, i choose ah rum mantra, breathing in on ah and out on rum,,it did build a slight pressure in the area's you described so i relaxed the focus on my breathing and it helped..
Hope this helps, but as i said i'm new to all this so i could be totally off here but you have some good experienced people here so i'm sure you'll find the answers.

Paul