Razz: Facing aggro on 5th/6th when ahead

[Zagga]

I have played razz for te first time this weekend, and played it seriously on a $0,50-$1 2 tables alot yesterday (about $50 up). I haven't read anything about razz except the rules so I don't know any real strategy and do what I think is the right thing to do (it doesn't seem to be a hard game). I only play starting hands with all 3 8 or lower, unless I have a A-3 up and everyone behind me has high cards up and it is folded to me (then I complete, bet 4th unless a high card/pair comes).

This is something I had happening a few times, on 5th I have a hand like (not an actual hand, just examples):
4A69T

And my opponent:
XXAJ5

I bet, opponent raises. I am lke wtf? I have T high, he obviously has J high at this point so I am ahead, and I usually just reraise.

supose He then caps and I call, and 6th is:

4A69T6

XXAJ5Q

Neither help to both players, I am still clearly ahead with Ten high against Jack high, but I only have a draw to 9 high while villain could have a wheeldraw. Villain bets out, I raise becouse I am clearly ahead at this point, villain caps and I call, planning on checking/calling the river whatever card I get.

River comes, villain bets and I call. Villain turns over 7 for a rivered 7 high and takes the pot.

Hands like this happened quite a few times. Do I overate me being ahead at these points? or is the villain a clear idiot? Maybe better to just call his raises on 5th and 6th because he has so many outs or indeed charge him to outdraw me?