Bevlin.
Putting on weight does take getting used to Trellism but as this is my 2nd pregnancy I'm less bothered this time. Is it your first?
I know in 10wks time after the birth, I'll lose a stone instantly, gain a gorgeous newborn and have humungous (for me anyway!) breastfeeding boobs- yay!
Just keep rubbing in the bio-oil in an attempt to keep stretch marks to a minimum.
I tend to get water retention towards the end too leaving me with a lovely, puffy looking face.
Bevlin, I find I can put more weight in the first trimester because of the feeling sick and so tired and food being the only thing that helps. I don't think 7lbs is much at 17 weeks, don't forget you have a growing placenta, more blood, little baby etc.
If you feel relatively normal now, (ie. not sick) then get back to eating healthily, loads of fruit and veg, good carbs and protein, water to drink, or caffeine free tea/coffee. Have your treats in moderation. I bet you get lots of exercise already running around after a 2yr old. I know I do with my 18mth old DS.