I Keep gaining weight and I'm only 8 weeks😢

I don't get it I walk 3.50 miles a day for exercise after work.  I generally don't eat after 6-7 and I only drink water occasionally I might have a lemonade or orange juice. I can't believe I have gained 15 lbs already I'm so depressed about it.  I'm 36 and 5'9 I was weighting 210 or so and now I'm at 226 😩.    Is this happening to anyone else?  Does the weight gaining tapper off I don't know what to do???? My bra size has went from a 36C to a 38.   I don't really look like my weight but I just want a healthy pregnancy