Is she pregnant now or what?

The probability of her becoming pregnant is very slim, but still there. I wouldn't worry about it unless she misses her period. Her being dizzy/having bigger than normal are more than likely just symptoms of her about to start her period. Remember, menstrual symptoms and pregnancy symptoms are very similar. So don't trip until she misses her period. Don't stress her out about it either because that can delay her period, making you believe she's pregnant when she's not. good luck