Had sex 10 weeks ago & used planb. im having pregnant symptoms (24/7nausea and bloating) but recently had a neg. blood test & heavy period. could i be preg?

Not if neg preg test: Home pregnancy tests are very reliable. If you have done one and it is negative then you can rely on it. Most likely this is just your first period after plan b. I would schedule a visit to discuss an effective contraception plan so that you dont need Plan B in the future.

Probably not: Have you had your period in the last 10 weeks? With recently negative pregnancy test 2.5 months after intercourse, assuming a standard sensitivity test (they vary widely), it is unlikely that you are pregnant. Plan b altered your hormone balance=> too much buildup of your endometrial lining. Now your are shedding it. Bloating common.If tired, light headed, see your OB to rule out anemia.